I have a late 2007 MacBook Pro (Santa Rosa chipset) 2.2 GHz with 2GB RAM. It has been a superb beast since the day I bought it but all this talk of the new MBP's and SL etc has made me long for a bit of an upgrade... I thought perhaps instead of buying a new laptop (Apple damn expensive here in South Africa) I would just upgrade the RAM. Will 4GB Ram make much of a difference with speed and multi-tasking compared to 2GB?? Also how do I know if the RAM is compatible? Will any 2GB DDR2-667 200-Pin Notebook Memory work or are certain brands only compatible? I can get cheap prices on brands such as Transcend, Hynix, Corsair, OCZ... Any advice would be more than welcome!