First of all, it's Glenn, not Mr. Roberts (being an ex-Air Force lieutenant, many moons ago, and having an ex-Navy type as a business partner, I try to avoid the Navy lingo!) I'm also on the downhill slide to 100, at age 54.
Next, a couple of general comments: I began trending toward lightweight packing because I wanted to simplify my hiking experience; I was tired of messing with gear: packing, unpacking, organizing, setting up, cleaning it after the trip, and generally keeping track of it. The lighter weight was a bonus. I tend to use main-line manufacturer's gear; some may be cutting edge, but none is really bleeding edge. I probably settled for more comfort than most light hikers, but I also never developed a taste for high-mileage days, with lots of goal-oriented hiking. (My biggest goal is to get back to the truck sometime Sunday morning; what happens in between Friday night and then is always good, even if the plan gets changed midday Saturday. I'm a CPA by trade; I come out here to get away from that regimented, targeted life I lead all week.) Finally, I hike exclusively in the lower Midwest: Ohio, Indiana, and Kentucky, with occasional trips to Isle Royale or Shenandoah National Parks. That influences some of my gear and especially clothing selection. Now for the gear:
Granite Gear Vapor Trail pack with a GG Cloud Cover silnylon pack cover - hands down the most comfortable pack I've ever used. The back pad, when the pack is under my legs, does a dandy job of extending my 3/4 Thermarest. However, I'm also experimenting with a Granite Gear Virga, using the Thermarest pad, lightly inflated, in its chair kit. The set is rolled just enough to fit down the back of the pack, in such a way that the stays in the chair become the equivalent of pack stays. It works great under 20 pounds, and OK up to 25. However, space is a problem on cool weather or long trips. (I've just about got figured out how to lash a few things - mostly clothes in stuff sacks - to the outside to solve the problem.) It saves a pound over the Vapor Trail.
MSR Zoid 1 tent, no groundcloth: I also tried the Microzoid, but found I wanted a little more headroom and room for gear. I usually swing my food (raccoons, etc., not bears), but everything else comes inside.
Marmot sleeping bag: depending on temperature, it's a Trails liner (summer) or Helium or Hydrogen.
Thermarest 3/4 length Prolite 4 pad and Lite 20 chair kit: as mentioned earlier, I decided the comfort level was worth it. In spades.
MSR Titan Mini-cookset - usually just the lifter, lid and 1.5 quart pot. The smaller pot stays home as extraneous. I've also found anything smaller doesn't do a good job as a sink for washing up or a reservoir to let silty water settle before filtering. A Lexan spoon always goes, and an REI lexan cup (the kind with measuring marks) sometimes goes if I'm having cocoa. (Usually, I just use the marks on the water bottle for measuring.) A butane lighter or matches in a small nalgene bottle (better than a matchsafe) and a hand-sized Paktowl for cleanup completes the kitchen.
MSR Simmerlite stove and 11 oz. fuel bottle, which I never disconnect from the stove. Both fit in the stove's stuff sack nicely and, so long as the system stays closed, there's really very little chance for crud to get into the fuel line. Lately, however, I've been experimenting with a Trangia Westwind and .5 L fuel bottle. I like the idea of a renewable fuel source, and no fussing with priming. The fuel isn't as efficient (but I don't take long enough trips for the weight to really become an issue), and it does take longer to boil water - but what else have I got to do? The jury's out on which stove I like better at this point.
MSR Miniworks filter, 1-quart Lexan Nalgene bottle, and 2-quart MSR Dromlite bag. The Miniworks has never given me the first moment's problem; it field-cleans in a very simple operation, and the direct attachment to the bottle makes it a breeze to use. I'm lucky that I can plan my water stops so I rarely need to carry more than a quart; I usually drink heavily at each stop, then fill the bottle again. The Dromlite is for carrying water to a dry camp (I like ridgetop views at supper); filled with air, it makes a dandy pillow. A second Lexan bottle goes along if I think I'll need to carry more than 3 quarts of water. (I know Platypus and Nalgene Cantenes are lighter than Lexan bottles; I've tried them, and had no problems. But there's just something about that bombproof rigid bottle that makes me regret it every time I've left it home. Strictly illogical, but I do it anyhow.)
Standard summer clothing: my clothes are 100% Patagonia, not because of the snob appeal, but because they fit me well and are comfortable. I've tried various house brands and other labels, but couldn't find stuff that consistently fit well. Patagonia does, for me; that doesn't mean everyone should use it. Go for fit. For summer, I wear a pair of Baggies shorts with a nylon liner, a Capilene silkweight T-shirt, Capilene liner and midweight socks in my Vasque Sundowner Classic boots (again: fit drove the selection.) I also carry a Dragonfly pullover, Specter rain jacket, and Supercell rain pants on every trip, plus a spare set of socks. As the weather cools, I'll add some or all of: a long-sleeve silkweight T-shirt, R.5 pullover, R1 flash pullover and pants, R2 Pullover, R1 glove liners, Digitshell gloves, and R1 balaclava. I may eventually add a down sweater for truly cold weather, but we don't get much of that here, and I don't go out in it when we do. (Tax season, not lack of desire.)
I also carry a minimal first aid kit (Motrin, Advil, bandaids, Bacitracin, and moleskin), toilet paper, and a sample-size bottle of hand sanitizer. I use a Princeton Tec Scout headlamp, Leatherman Micratool, and Silva Companion compass. I usually don't take a watch (again, trying to escape regimentation) and never take a cell phone, PDA, GPS, MP3 or other alphabetic electronics.
My menu for 2 night trips is: 1 packet of oatmeal for each breakfast, a package of Uncle Ben's Flavorful rice with a 3-oz. foil pack of chicken mixed in for each supper (or a 1-person freeze-dried entree), a Snickers Marathon bar, Clif bar, and 2-oz. pack of beef jerky for each lunch, and a Tiger's Milk bar for each morning and afternoon snack. I drink water as my only beverage (except, once in a while, I'll give in and take a packet of hot cocoa for the evening.) I normally take no emergency food; the woods around here aren't big enough that you'll end up lost for days and days, and I rarely if ever stray off a trail. The food may be a little light, but I've found that I don't eat as heavily as I used to and this keeps me plenty full. I don't seem to have any problem with sustained energy, or energy boom-and-bust cycles either.
The weight for a summer weekend, including food, water, and fuel, is 19.5 pounds. Base weight is 15. (Both weights are for the Vapor Trail pack; with the Virga, deduct a pound from each.) Hope this helps. Let me know if you have other questions.