I would have to recommend you get an Apple laptop.
They are intel based, so if you are a Windows user you can run it natively on the processor, but the real beauty for web cam conferencing I definitely recommend the Mac laptops. They have built in iSight webcams with great quality and using iChat you can do video chats with multiple people like this:

You can also share your desktop and showcase your documents and collaborate online with other people you choose.
iChat is very powerful on the latest release of the Mac Operating system, OS X 10.5 (Leopard), which is included with all new computers.
You can find out more about what you can do with iChat here:
http://www.apple.com/macosx/features/ichat.html
And you can also use Skype or any other program if you prefer.
Hope you get a mac and LOVE IT!
Itay.