when should i get a new mac laptop?

i need a new computer – ideally asap (say a couple weeks), but with a good argument within a month or two.

[more info, if desired: i just started grad school this week, and i already tell that it’s gonna be a little rough with my totally-full HD (yes, i have externals), non-functional Word (macros which infected and i can’t get rid of them), and non-functioning iPhoto…... of course there are computer labs, but that’s obviously less convenient, especially for composing, which is what i do. huge files, specific software, noise making….]

now that i’ve started school, i have the student discount. i’d planned to buy around now, but there was that discussion last week about Leopard’s release in October—any updates on that? i can see the sense in waiting for that, but what if it’s postponed? is there anything else i should know about in the upcoming weeks/months to factor into this decision? thoughts?

and of course if you have thoughts on specifications that’s helpful too!