Bass players = sexy.
Anyway, it's important to know that if you do choose bass, you'll be adding to a market that needs bass players, but, you'll also be paying more for your instrament and possibly your gear. Not that this should be a deciding factor, but sometimes it can be a big deal to new players.
It's also important to know that bass is hard to get started on -- it already hurt guitarist's fingers like crazy when they start out, think about playing on strings that are 2-3+ times as thick. This is especially important if you have small hands (though there are basses and guitars designed to suit this).
So, with all that said, most people will probably want to (and do) start on guitar. But, if you're really up for being an original and sexy person, go for bass, and whichever instrament you choose STICK WITH IT. Don't quit in the first two months like all the other unsexy people out there.