Macbook Pro 13 inch, 2011 or 2012?

I can't speak for the 13" MacBook Pro - I've never had one (I have the 2012 15" MBP). However, I'd suggest waiting if you can. It'd be a good idea for the latest 13" model to become available in your area.

Without a doubt wait, the HD 4000 is up to 60% faster, which relative to the HD 3000 is quite a difference, can be the difference between a game being playable/not. USB 3.0 is around 10x quicker, which is definitely going to future proof yourself a little, so for the same price it is without a doubt worth waiting for.

Its what I have done!

For the 13in I'd wait

Wait.

As others have mentioned, the Intel graphics chip is leaps and bounds better than the previous generation. But the new generation (Ivy Bridge) Intel CPU is also much better than the previous generation's Sandy Bridge Intel chips.

Check out the GeekBench scores. There are 2 2012 13" models (reflecting the two base SKUs you can order) and then both of the previous generation's. The high end 13" for 2012 clocks in at 7838. The high end late 2011 13" (with an i7 processor) scored a 6973. Conversely, the low end 2012 model (with an i5) nearly matched that with a 6687. In other words, this year's worst model is a stone's throw away from matching the best that the previous generation had to offer.

http://browser.primatelabs.com/mac-benchmarks

If you really can't wait for a new one, be sure to get the higher end old model. Its easy to differentiate from the low end because it sports the faster i7 dual-core processor. Upgrade the RAM also.