Haven't read the other posts here, so sorry if I repeat something.
I'm faily certain that at most schools the LSAT counts somewhat more than GPA. It could be somewhat true that an admissions committee may wonder why an applicant w/ a low GPA didn't apply herself more as an undergrad. But it's a lot better than an admissions committee having doubts about whether a law student can actually do the work.
A good GPA, especially at an undergrad school without a great reputation, is also seen as a matter of effort -- rather than intelligence -- by law school admissions committees. Most law schools are less concerned about whether an applicant will do the work (students being prepared and doing homework isn't a big issue at most law schools) than whether they can.
Of course, this doesn't mean that an undergraduate record doesn't count -- far from it. A record with difficult classes is especially helpful (and necessary at any top school).
If you're interested, the LSAC has formulas used by law schools to come up with admissions indexes. They're posted on the LSAC Online Services website (you have to sign in though). It will prove what I'm saying, btw.