I'll probably get beaten to death for saying this and it's not exactly a netbook, but I have an Acer Aspire 5553g that I got for £538 and it's damn good. Pretty much silent, not exactly light but light enough that I'm able to take it to college with me every day.
Specs are as follows:
15.6" display, 1366x768
AMD Phenom II X4 Mobile
ATi Mobility Radeon 5470 - 512MB VRAM (also has an integrated ATi Mobility Radeon 4250)
4GB RAM
320GB HDD
Might not be what you're looking for, but it's a pretty good laptop in my opinion (although those Lenovo laptops look damn nice, but in my case I was on a strict budget - £540 in my case).