I have both the GN and the S2. Both good phones. Screens are both great.
It sounds like the OP went with the Gnex....good choice!
Biggest weakness is the affiliation to the carrier.
I prefer the GN, just do to software. The Hardware is similar, they are both fast. The GN has a pretty bad camera. No SD card and (for me) only 16GB(Which I have learned to live with)(Your lucky you get 32GB...Nice!) I also love the bigger HD screen. I compared it to the One X and to my old eyes I could not see a big enough difference to care about. So it comes down to how good one's eye's are. At 720P I can no longer distinguish pixel's.
Its funny a number of folks have talked about the faster updates with the GN. If its connected to a carrier they get delayed like every other phone.
Case in point I have had Jellybean on my pure Google GN since it came out in early July as an OTA update. No carrier affiliation is a dream. I won't ever go back to a contract phone.
Some folks think stock JB is boring, I like the rock solid reliability.(and not having to take it back to stock to get the next OTA). Looking forward to the New Nexus(Or Nexii) coming out in few month's.
Honestly though, the snappier your GN is on ICS, the less likely you will notice a difference in JB. I couldn't notice any difference in "Butter". Others did notice a difference....