Second m4/3 body
Fast forward one year and I'm still really happy with the e-pm1 and 20mm 1.7 combination and started looking at second bodies to supplement my gear. I'm ashamed to say I felt the need to go back to a bigger sensor to try with a fixed focal length prime, hence my decision to pick up a cheap NEX-3 in addition to a Sigma 30mm 2.8.
I'm now looking to sell the Sony and get a second m4/3 setup.
I'm not fussed about the latest body and just want a reasonably fast prime to go with it. I would go for the GF1 or GF3 but was wondering if I will be ok without the stabilization?
Don't be ashamed about anything, so long as you learn something from it. I went through a Nikon D300 and a few lenses before I came upon MFT and decided it's the system for me (I've sold my Nikon gear).
You already have one fast MFT prime, the 20mm. That's my favorite lens, and the Oly 45 f/1.8 is another fast, reasonably priced choice that would complement the 20mm well.
Forget about the GF1 and GF3. If you're on a tight budget, you could pick up a nice used GX1 for cheap and it would be better than either of those. Or get one of the more recent, but not latest, 16MP Oly bodies as suggested by others.
Don't worry about no stabilization with the 20 or 45 and a Panasonic body. They are fast lenses, the GX1 does 1600 ISO reasonably well, you can get great shots without IS.
The big thing is to think long term. Bodies come and go, but good lenses delight for a long time.