Here's a report from Treonauts on measured battery life with a new Seidio 2400mAH battery. The figures in the brackets, I added based upon a simple ratio for the regular 1800 mAH battery

http://blog.treonauts.com/2006/04/treo_battery_li.html

"Using a few software battery measuring tools, testing hours of music and movies play as well as driving around with my GPS combined with a few calculations yielded the following results for the Extended Battery (the standard Treo battery results would be about 30% lower):

* Battery life with music playback in background mode
o 730 [550] minutes / 12 hours and 10 minutes [9:10]
* Battery life with movie playback in full screen mode
o 260 [200] minutes / 4 hours and 20 minutes [3:20]
* Battery life with GPS Navigation in full screen mode + active Bluetooth
o 230 [170] minutes / 3 hours and 50 minutes [2:50]"

I have no idea whether his was a CDMA or GSM Treo or whether he had phone on in the background. With phone off, I would think battery life on CDMA / GSM would be the same. With phone on, GSM would get longer life.

I tried to post a comment asking same , still waiting for "activation e-mail"