Each day I love my GX1 a little more...
Before I picked one up to replace my two years old GF1, I already expect I'll like the better high ISO performance and that bouncable built-in flash a lot.
On day one, I already like the tilt sensor a lot. I expect it will save me a lot of time on the ruler tool in Photoshop. Later when I paired it with my 7-14mm, avoiding distortion is just real easy and fun.
For me, the better high ISO performance makes the 20mm/1.7 a lot more usable. ISO 1600 at 1/60s opens up a lot of indoor and nightime photo opportunities. I did not use the 20mm much on my GF1, now it is one of the two lens I carry with my GX1 all the time. The other lens being the 14-42X.
Thank God my 14-42X appears to perform well, no double images or softness in all my 42mm 1/160s shots as far as I can tell.
The GX1 touch screen is growing on me over time. I have settled on a mix of features from the quick menu, Fn buttons and touch screen that appears to work well with my style of shooting.
I just read from another post that GF1, G1 and GH1 are the only m4/3 bodies not able to auto focus on some 4/3 lens. I do macro shots with my Olympus 35mm 1:3.5. Getting the lens at the right distance from the inanimate object I shoot and manually refocus the shot on my GF1 after every little adjustment made on the object placement was very time consuming. On my GX1, the 35mm focuses slowly, but at least it does and does so accurately, no matter where on the LCD screen I touched focus.
I still love my GF1 and am keeping it for sentimental value, but my GX1 is just amazing. Well done Panasonic! Do please get to the bottom on that double image issue on the 14-42X real fast.