A link to an interesting study from just over a year ago that proves a few points made in this thread:
1) As a general rule, the cheaper a laptop is the more it will break down.
2) The failure rates for most laptops are very similar...except HP.
3) Saying Apple has better internal hardware is wrong. A hard drive is a hard drive, regardless of the wrapping. Where Apple does shine, however, is the screen, keyboard, case, etc. Oh, and the OS.
IMO, your buying decision should be based upon overall value, not just reliability. What is the warranty like, what is the process like when something goes wrong?
At the end of the day, just do as suggested here and read some detailed reviews of specific models as quality can vary greatly.
http://netbookboards.com/2009/11/17/...-failure-rate/
http://www.itp.net/578466-asus-and-t...-laptop-brands