I wanted to report my first day with the seidio 1600 battery...
I had my phone on since 7:30am, its now 10pm and the phone just completely lost power. For the past hour I have been playing videos trying to kill the battery so I can go to sleep. I also started using a bunch of apps for the past hour and set the brightness to full. For the rest of the day I had GPS, Bluetooth on, and brightness at like 25% which is plenty bright to me. Other tasks during the day included taking about 20 photos, multiple web searches, odd facebook checks, and a number of calls. Tried to keep it as normal use as possible for me. I think this life is fine, and I had to really work the phone at the end to get it to lose power.
Being this is the first day and first full drain I see the life getting better from what I have ready about these batteries. Seidio even states on the card that comes with it that it takes a few cycles before the battery life is optimized.
Just wanted to report my experience, and that I am happy with this battery life.