Harris, there are a lot of new features from version 7 to CS4. However, the vast majority of the tools that I cover in my PS7 tutorials work the same in CS3 and CS4. In other words, my tutorial is pretty much backward-compatible. I have had people use my tutorials with CS3 and CS4 and tell me that they had no problems following along.

I would recommend you pick up a copy of JUST my Photoshop 101 course and see if you have any problems. If you do, you can always invoke my MONEY-BACK guarantee and I'll either refund your $5.99 or give you a credit for when my CS4 class comes out (your choice).