im fine with my 710. even better when i've got my 7.8 update. my only concern is the lowlight shots. terrible. but given the specs, i got used to it. i will only consider buying a wp8 if things get better. apps, 41mp camera etc... so far im satisfied with my 710 :)
My Lumia 710 doesn't have the same problems relating to battery consumption. Mine has about 7-9 app running in the background, 3 e-mails set to sync at 15-anytime time intervals and I get about 36+ hours of moderate usage.
Photos from the 710 are less-than-stellar at best, but video quality is superb for a 5mp shooter.
...and of course, the usual WP7 OS quirks like low volume, "other" memory taking up most of the space, etc.