NEED HELP which laptop to choose :)

There is always a new laptop around the corner though. A retina 13 inch may come in October, but that's still 4 months away. If you feel you need a retina screen (by the sounds of your usage you don't) then sure, wait. But if it doesn't come then what do you do? Buy the MBA 4 months later...

I just bought a 13 MBA. Was deliberating over the MBPR and could afford it, but decided against it. Decided it's not worth dithering and wasting time

The current laptop you have is fine IMO. The main bottleneck in performance would be the RAM and HDD.

You can really boost up performance by putting in a 2.5" SSD instead of the HDD. Sure, you'll have less space, but it'll feel like a new Mac. Keep in mind that the MBA is only 2.0 GHz, it's the SSD that makes it fast and snappy.

If you absolutely need the extra storage, you can replace the internal ODD with a boot SSD to get the best of both worlds. Optical media is going out pretty quick, so no real need for the SuperDrive. Plus, you can get an external case for the ODD that'll connect via USB.

RAM-wise, you can pick up some chips for very little money. I don't know about the restrictions on the 2008 model, but you should be able to get 8 gigs very cheap, provided that the motherboard is set for DDR3.

[EDIT] Also - there's been no cosmetic change, so you're not really missing out on anything. Unless you absolutely need the new ports / upgraded FaceTime