Yes - they still have a few in their warehouse in AZ. Here's a quote from Meridian Design customer support:
"Yes, Camelbak has now leased the rights to the Aquastar with modifications that our engineers helped them develop. I have no idea when they expect to release it for retail or what the price will be. We/they have been working on the modifications for some time now. We still have some Aquastars left but they will take over production pretty soon. We still own the mUV. darleen, customer support"
I've truly been thrilled with the AquaStar. I'm lucky in that I'm not drinking from mud puddles or drainages below livestock. For the most part I believe that I'd be fine drinking directly from my sources in the PA mountains without any treatment, but the AquaStar makes treatment quick and easy so why risk it? When we need water we are able to generate a liter every two minutes (including filling the bottle through the mesh prefilter, the 80 seconds of treatment, and then pouring it into the destination container). I've used the one AquaStar to supply the water for a group of four without any problems.
I've only had two issues with the AquaStar and they were both entirely user problems. I lost the mesh prefilter with my unit (I've since attached my replacement with a wiretie which works well). The second problem was that my batteries died when I was using the unit in bright sunlight and couldn't see the bulb glow. I assumed it was working and it wasn't until later that I realized that it wasn't. I didn't get sick and I carry spare batteries anyway (1.2 ounces for the two of them) so we were fine for the rest of the trip.
Although I haven't used it yet, I just purchased the mUv and am looking forward to using it on my next hike (knowing, however, that at least one of my hiking buddies will be carrying the AquaStar). It was driving me nuts that the AquaStar was the 4th heaviest item I carried (at 8.3 ounces - less than my GG Murmur, SMD Gatewood Cape, and my UL60 quilt but heavier than everything else). As long as I'm not supplying the water for the entire group I believe the mUv will meet my needs and save me at least five ounces.
One thing I will miss by not carrying the AquaStar is the easy ability to measure water to boil (particularly for oatmeal). Although my wife thought I was nuts, I've solved that dilemma with a suggestion I saw in this forum - to carry a baby bottle liner for measuring. Looks perfect!
I'm a three-season hiker so I don't have any experience using the AquaStar in below-freezing conditions. I can say that I didn't have any problems when air temps were in the low 30's, but that's the extent of my experience.