Overall, I'd go with the Zebralight... the headlamp feature is just too good to pass up.
But, other notes:
Personally, if you're strongly considering the LD10 and want that size/format of light (AA, clicky), I'd choose the 4Seven's Quark AA over the LD10 any day.
The Quark has several things you will probably appreciate while backpacking:
1- Super low moonlight mode: The moonlight mode (0.2lumens?) is adequate to read by. If your eyes are adapted to the dark, you'll be surprised what you can do with this mode. And as a bonus, using it won't totally destroy your night vision. And the batteries last for days and days on this mode, it's fantastic.
2- Better pocket clip: The Quark pocket clip is a much better/reliable design if you're actually going to use it. The Fenix pocket clip on this one is sort of an afterthought that clips onto the light.
3- Note that 4Sevens rates their lumen output differently than Fenix. 4Sevens uses a more honest "OTF" or out the front lumen output that is actually measured and includes light loss at the lens, whereas Fenix is quoting an estimate of how much is being put out at the LED. So, 100 4Sevens OTF lumens > 100 Fenix emitter lumens.
4- 10 year warranty on 4Sevens is a nice touch. David Chow/his team at 4Sevens back up their products well and are easy to get a hold of.
(As you can tell, I guess I'm kind of a 4Seven's fanboy, but I just think they make very carefully thought out products. All the above being said, the LD10 is also a great light, so you wouldn't be making a bad choice either way.)
If you want AAA format, like the LD01, also consider the 4Sevens Preon ReVO... a bit more money, but it uses a more advanced power regulation scheme (current-controlled rather than PWM, which is hard to come by in such a small light). This results in great battery life for its size on the ReVo. Same comment about 4Sevens using lower-sounding OTF lumens ratings applies here.