I've got a Toshiba A200-1m8, Core2Duo 1.8ghz with ATI Radeon HD2600 Mobility. Had it for 15 months now. Irritating thing is that AMD's Radeon drivers don't support it by default. I have to run that mobility modding tool to get them to install for my card. It's either that or wait a several months each time for Toshiba to release an updated driver version.
I hope the support for the HD4000 range is better than I've experienced for the HD2600!