Ok, I've done a *lot* of Googling and have discovered that the video chipset (Intel GMA 500) is causing huge problems in the Linux world.
Any laptop with this chipset is almost useless in Linux as Xorg runs very slow using the plain vesa driver.
There has been rumours that the Intel guys are going to start working on the driver and get a fully open source 2D implementation out in the next few months - but I don't see this happening. The GIT repository for the driver hosted at Intel hasn't been changed since the middle of last year.
Very depressing news indeed. I cannot find *anything* that looks as good as the Sony Vaio P series - its beautiful. =(