This message is for my dad who is still getting his email setup while transitioning to a dialup modem. He is looking for insights from others who have used his particular digital camera. Of particular note are battery life and viewfinder issues.
The battery life issue is a recurring them in most reviews. They're all aware that HP does not recommend using rechargeables. Yet, nearly all have used NiMH with great success. They offer the reasons they think HP is wary of NiMH's with this particular model.
At epinions there was this review which was particularly optimistic. You can read all 15 reviews here. They range the spectrum from hating the camera to liking it if you get rechargeables.
The other place I often look for "common man" opinion (as opposed to professional reviewers) is the Usenet. Between Usenet, epinions, and google, it's scary how much info you can find. I find them very useful whenever I'm going to make a significant purchase. Anyway, over the past year or so, the topic of rechargeables has come up on Usenet several times in the context of the HP 215 digital camera. Follow the links on this page and you'll get several folks' opinions on using rechargeables.
The bottom line seems to be that nearly everyone has used NiMH (nickel-metal-hydride) batteries successfully. These are different from NiCd (Nickel Cadmium aka NiCads). Don't get the two mixed up. From what most folks are saying, the power regulator of the camera is such that if it fails, the current driving capacity of NiMH batteries can fry the camera. NiMH battery voltage/current curves are such that they'll drive current under low voltage. An adequate mechanical analogy might be the torque/rpm curves in an automobile engine. At 1200 rpm, a 200 horsepower V8 can typical haul a lot more than 1200 rpm on some heavily tweaked (turbo, multivalve, etc) 200 horsepower inline 4 cylinder. The torque curves of the V8 are flatter, less dependent on rpms. In a similar way, the current drive of a NiMH battery is flatter than your average alkaline, even though the alkaline has slightly more voltage (1.5V vs. 1.3V) . In the presence of a short or regulator failure, the NiMH is more likely to keep chugging, so to speak. Most seem to say that if you should be so unlucky as to have this happen, don't mention to HP that you used rechargeables.
Hope this helps and hope you get your email working again soon...