There are many reasons to sell, or keep as well ... many would have bought on impulse, easy to buy, easy to sell, it's not like it costs $5000++. There are no manufacturing defects reported, so far, if that is your concern.
But I guess you might want to start with a DSLR, it should be easier to use, more lenses, accessories.
IMHO, the E-P1 is really not for newbie photography enthusiasts, even if they say so. It cannot even capture moving children or pets easily. A Panasonic GF1 might be better, but so may be the EP-2.
Basically, I concur with the E-P1 reviewer from dpreview, in his "Overall conclusions", and "Who's It For ?"
http://www.dpreview.com/reviews/OlympusEP1/page37.asp
Or the Cnet reviewer's assessment:
"Olympus is targeting 3 types of shooters with the E-P1: dSLR owners looking for a compact complement, enthusiast photographers who like that rangefinder feel of compact models like the G10 but who want interchangeable lenses, and snapshooters looking to step up from a point-and-shoot model but who are leery of the bulk of a dSLR. I can't really recommend the E-P1 to folks upgrading from a point-and-shoot, since the biggest motivation there, in addition to wanting better low-light photos, tends to be a desire for better performance to shoot kids, pets and sports. On the latter count, unfortunately, the E-P1 simply doesn't deliver. But, I think the first two groups would be more forgiving of the E-P1's performance--either because they have tricks to compensate or because they have a faster camera somewhere for shooting action--and most appreciative of the design and photo quality."
http://reviews.cnet.com/digital-cameras/olympus-e-p1-silver/4505-6501_7-33688027.html
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