I have had numerous friends ask if they should get the i7 instead of the i5 and here are my reasons why I think the i7 upgrade is a great deal:
-If you plan to keep you MBP for a long while the i7 will allow your MBP to remain faster in the long run.
-People will complain now that its a waste of money and that the speed isn't that great but it may come in handy down the road. It will make 10.7, 10.8, and 10.9 faster and who knows what software you might be using in the future.
-The cost is roughly $150 if you are a student and $200 for a regular customer. I think that it is a good investment in your MBP for longevity as well as resale value should you decide to sell it later on for a new model.
-No matter how you state it, analyze it, review it, criticize it, argue it; the i7 is a faster CPU than the i5. Its also not upgradeable so its a decision that has to be carefully made. Again, speaking from the perspective of a long term purchase, I think its a good deal.
Good luck!
-P