I have a w90vn with the Nvidia 9800 in it and was wondering if it's possible to swap the processor or the graphics card as i'm now seeing machines with faster components but not such a nice screen or overall setup.
The Core 2 Duo T9600 is about the top end of the X38 chipset / PGA478 socket food chain. There are no available CPU upgrades that really make upgrading worthwhile.
The Asus W90Vn uses a MXM video card connector which, in theory, makes it possible to upgrade a video card. In reality it just makes it easier for a repair tech to change out the 9800M GS card if it ever fails. A upgrade card would have the MXM edge connector, but would also probably be shaped differently, have different power and cooling requirements.
To know for sure - I think you'd want to ask the same question in the Asus support forums.