Toshiba has got heat problems, which until now is not resolved.
Not trying to ruin their business or what, but after walking around
some laptop shops selling Toshiba laptops, I still find that they
are freaking warm despite being in an air-conditioned room.
Fujitsu is good, but prices may not be to everyone's liking.
As for Dell... no comments. Since the bad battery incident, I'm
seeing improvements. Good for Dell. You heard your customers.
Acer... either it lasts beyond the warranty given or it dies
after the warranty ends.
NEC... not many people using, but I don't hear much complaints
either.
HP/Compaq... quite good in my opinion. Same for Packard Bell.
Although Packard Bell laptops specs aren't that attractive.
Sony laptops - some have great specs, but they also come at
great costs. Even some lower end ones also cost pretty much,
perhaps due to the branding.
As for Macs... no idea. tamago will know more... see what he has
to say.