the comedy kit lenses, so if you can afford the E330 I'd consider a cheaper body and a proper lens.
As for the two cameras - they are so different; if you want the one you won't want the other.
My kind of phtography is arty stuff and landscapes, so I'd want LiveView. If you mainly take pictures of your family and pets in low light, the 350D is much better.
The direct Oly equivalent of the 350D is the E500 of course, which I have, along with the E1. The E330 is an E500 modified to provide LiveView.
The 350D is probabaly a better camera technically than the E500 - the viewfinder isn't so cramped, it does more fps, and the high ISO noise performance is better.
However, to get a good picture you have to:
Have the camera with you.
Have it correctly set.
The Oly 2x crop factor (which, as various people endlessly point out, is a misnomer, because there is no crop) makes for a much lighter system than the APS-C Canon (let alone the 35mmFF), so, if you buy some lenses, you are much more likley to actually be CARRYING your cameras if you get an Oly. Heavy kit, after people have played for a bit, tends to be left at home...
The Canon brings the baggage of earlier Canons with it, being clearly related to the (horrible) Canon EOS film camera I have here, and it really is an evil thing to hold, use and set. With the Oly, press the OK button, and you have a quickly navigable backscreen where almost anything can be set quickly. The Canon is menu driven, with all that means in wasted time and lost shots.
I've nothing against Canon, and now my needs have changed and a luggable, expensive lump is a valid solution, I'm looking at a 5D if Olympus doesn't come up with a high end camera soon (which they probabaly will - we should knbow in a few weeks). But I'd not use a 350D - very awkward camera, and there is no shortage of competition. If you wnat a Canon, why not a 30D? I've never used one, but that is a very powerful camera I'm told.
Back to the E330...
The weakness of the 330 is that it is based on the cheap and cheerful E500. If you do arty shots, I reckon LiveView is to kill for, and I'd love it. If you don't, then you are paying too much for an E500 and/or missing the chance for a faster, more powerful camera. It would be my choice, but it isn't for everyone. The unimaginative shooter isn't going to get mcuh from it.
If I wanted a cheap entry level camera like the 350D I'd consider the E500, the D50 (only 6MP and nastily cut down, but good quality and nice to use), the Pentax *ist (6MP and menu driven, but great viewfinder and practically being given away).
If I were prepared to pay a bit more I'd consider the E330 (really a question of whether you have the imagination to use LiveView, or just want straight shots), the new Sony A100 (looks good on paper), or the D80 (nice new toy, looking good).
With the greatest respect, coming up with a shortlist of two such different cameras as the E330 and the 350D suggests more thought needed. Just my opinion.
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