I ordered a i7 model an received it today. If you're interested, here you can find my experience. Seems to me that the i7 will be the better choice. The 400MHz more in base-clock will be noticeable when plugged to an external monitor. Also it will be noticeable in the overall response of the system if you worked on a i5 model before.
I will have a look to it this weekend, but it seems to me that I will stay with the i7 model.
cu
SchodMC
Good choice!