Well although the product names have changed, not much else has really.
Intel cpu's are still better than AMD. A new intel cpu is coming nehalem which needs a new socket so don't bother buying a new mobo as these drop at the end of the year. Not sure what amd have planned.
nvidia cards are still better than ATI. nvidia are re-releasing various revisions of the g9x core which is a smaller tweaked g80 core. ati have got their act together to an extent but it is pretty much the same; they do well in 3dmark but IRL + AA they don't perform as well as nvidia.
The GT200 is the new single solution due end of Summer. Specs are unconfirmed but what I have read it will be an actual single card solution 10-15% faster than the 9800GX2. Before that drops there will be another product which is another revision of what we have, die shrink etc.
ATI have the r770 coming which I can't remember much about lol.
ddr3 is faster than ddr2 but is still pretty expensive, although it is coming down.
solid state drives (ssd) cost the earth so normal HDD are still the solution. 750gb/1tb drives are cheap enough now with 32mb chache perform pretty well.
Thats all from memory and written in a rush but google whatever you want to know more about you nublet lol