This Macbook in the ad is not the newest macbook with the new look but the 1 generation older macbook with the old design. You know it because of the 2.13GHz processor and you can check it here
http://www.everymac....ex-macbook.html.
I prefer the old look but it doesn't have the nice glass trackpad with the multi-touch gestures and the unibody design. Also this model comes with Leopard when the new OS from Apple is Snow Leopard. I too run Leopard on my iMac but I'm thinking of upgrading it to Snow Leopard since it only costs 30e.
You can buy yourself Microsoft Office for Mac 2008 and it costs 105e or Apple iWork for 80e that has the counterpart of Word, Excel and Powerpoint. I had the iWork trial and it was very nice to use, you'll get it too if you buy the Macbook. If you already have a Microsoft Office license for Windows I suggest you to install it on your Boot Camp (Windows) partition like I did and use that. Sure you need a Windows license too. Also there are free options like Openoffice and NeoOffice that work on a Mac and can replace Microsoft Office. Generally talking about the software for Mac you will be able to find all Windows counterparts that usually feel even better than the ones you're replacing but if you do CAD you're out of luck. I don't think you do since you didn't mention it so no worries.
if you install Windows on the Macbook along with OS X you will be able to play SOF2 MP Test easily with it and some of the newer games with lower settings. Here are some benchmarks done with that 9400m gfx
http://www.notebookc...-G.11949.0.html. You'll be able to play some Windows-only games on OS X with
Crossover but it costs a little and the performance is not as good as running the game natively on Windows.
Anyway, the Macbook in the ad is reasonably priced and I think it is a good deal for 699e. I would buy it too if I was looking for a low-cost laptop.
P.S. Once you switch to OS X I don't think you will miss Windows just like Charles told.