i happily owned a canon xti body with 70-200 f2.8L is & 17-55 f2.8 lenses for 6 years. the size and weight finally got to my back. i'm not a pro photog, just a dad who loves taking pix of his kids playing sports. i've since sold the lenses to purchase a µ43 system. i also borrowed a panasonic gh1 with the 20mm f1.8 pancake lens before purchasing the oly e-p3.
my purchase decision came down to the panasonic gx1 vs. the olympus e-p3 ($799 with the 17mm f2.0), and went olympus because of in body stabilization.
PROS
* lightweight. your back will thank you.
* compact. i easily fit the oly e-p3, 45mm f1.7, 17mm 2.8, and panny 14-140mm, 100-300mm in a lowepro 100 sling.
* hd video in avchd or motion jpeg
* high iso, i shot my daughter's night soccer playoff game at 4000 iso with acceptable graininess (max 128,000).
* in body stabilization, great for prime lenses without is.
* acceptable built in flash, mainly for fill
* compatibility with canon external flash (with loss of some auto settings)
* acceptable battery life (but do always have 'at least 1 extra charged battery on hand)
* full aperture, shutter, and manual controls
* special settings (fireworks, portrait, night, etc.)
CONS
* focusing in low light takes some time
* if set to continuous autofocus, shutter lag is unacceptable
* menu system is disorganized / confusing, not as intuitive as the panasonic and canon systems
* occasionally exposure is off (sometimes way over exposed or under exposed)
* i'd rather have the panasonic 20mm f1.8 instead of the oly 17mm f2.8. oh well.
* when videoing, the crop factor jumps up, so you can't rely on what you see to compose. try pre-videoing to get an idea of the crop before actually videoing.
* no articulating screen
i used to lose lens caps all the time. try these lens cap leashes (hmm, used to be $3.00 for five, it's currently $7.50). cut off the adhesive "plate", it's useless and falls off easily. instead, drill a tiny hole into the lens, thread the string in, and tie a few knots to secure the string.
5 LENS CAP LEASH! LENS CAP HOLDER/SAFETY CORD FOR SONY CANON NIKON OLYMPUS PENTAX LENS CAP, SAVE!!! $$$CONCLUSION
i agree with the above reviewers, there is no such thing as a perfect camera. but if you prefer something lightweight with in body stabilization and the flexibility of interchangeable lenses, the oly e-p3 is the way to go. happy shooting!