Interpreting compact camera battery metrics

Hello. This isn't specifically tramping but I figure people here will have some experience with cameras and camera batteries. Have compact cameras reduced in effective battery power capacity since the AA days, or am I mis-interpreting the metrics? My last couple of trampey cameras have been a Canon Powershot A710 and then an A720. Both awesome little cameras albeit now dated, and both of which take AA batteries. With them, I've never had any low-battery-capacity issues as long as I stuffed them with 2x 2500 mAh NiMH rechargeable batteries, and kept a charged spare set just in case. I never thought about this objectively until now that I need to compare it, but review sites such as http://www.imaging-resource.com/PRODS/A720IS/A720ISA6.HTM rate its CIPA battery life for that type of battery at between 400 and 900 shots, depending on the whether the LCD is switched on at the time. (Unlike today's compact cameras, they still gave it a viewfinder.) AA batteries are dead in the compact camera market replaced by the more compact and light-weight lithium-based camera batteries (I'm sure others know more than me which is why I'm asking), and the sorts of cameras I've been looking at are these ones: http://bit.ly/VM0lG0 If you scroll down the page, the CIPA battery life stated for these cameras is only 230, 320 and 260 by comparison... and according to the reviews, the one in the middle is considered really really good in today's compact camera market. So I'm starting to get concerned about what to expect, especially since camera batteries these days aren't as easily bought on the road. Obviously battery life depends on how you use the camera, but I'm looking for something that'll last at least as well as my current camera if I use it in a similar way. Has effective battery power really gone down-hill from what was possible with AA batteries, or is there something about the CIPA standard which has changed over time that I'm mis-interpreting here?