I will give you what I would look at when getting a Apple laptop and things to consider.
1) Gaming: Macs are not for gaming, period. So if your wanting something to play HL2 or Doom 3 then this isn't what you want.
2) Software compatiblity: Because the current macs are on a different OS and Processor Arcitecture you will have to find Mas OS versions of software. This can be a big problem for some when you have a bunch of windows machines and when you buy a program you want to use it on all of them. You will have to get Mac software. But I do know that Word has been ported to Mac and maybe even Open Office has as well.
3) Cost: They arn't the cheapest laptops out there.
1) Form: The are usually light notebooks with good battery life. This is at least the ones I have encoutered. People who actually own them could probably tell you better.
2) Mac OS: If you like the Mac OS system, then you would like a Apple or a pc with linux. Some preople really like thier operating system.
3) Power: Alot of the ones I have been around are pretty powerful little buggers. Not to say that PC versions arn't powerful too. I am not going to start a flame war with AMD vs Intel for what laptop processor to go with. But I do know Intel has some Powerful buggers as well with low power consumption.
What are you going to use this for? Writing up papers, surfting web, playing games, programming? I know for games Apple isn't your answer. If you are doing programming (i know quite a few programmers who really like thier Apple laptops) then it could be good. Same with web and email and music. While Itunes and Ipod can work with windows, you just might want that cool computer to go with them all.
Well, I hope that gave you some things to look at.