I (also) have both, and it's important to note that the E7 camera is the EDoF variety, whereas the N8 has autofocus, and the EDoF is pretty painful, IMHO, if you like to take really nice (N900, N8) macro photos.

I like the E7 keyboard, but I still prefer the N900, and the X/Shift/Ctrl? placement on the E7 keyboard is especially irritating.

The readablility of the E7 screen is nice, but the 640x360 resolution and the overall look and feel, fonts in web browser, email, etc... remind me of my Razr v3xx, in comparison to the N900 w/X11, higher screen resolution, really nice font handling, anti-aliasing, etc...

I also like 'conversations' (SMS) and email on the n900 a lot more than the Symbian^3 implementations, but I'm still curious to see the evolution of Symbian w/Anna and Belle, pending availability in the US.

And to be fair, my N8 and E7 mostly just sit in a drawer, and my perspective favors 'linux in my pocket' over any particular 'phone' interests, and I still have an N810, but the latest Qt 4.7 updates on Symbian^3 still make Symbian^3 interesting for development.