I don't think the degree you do matters significantly as far as journalism is concerned. IMO, knowing the subject matter you want to write about and being a decent writer will land you a junior position anywhere, and experience will take you upward from there.
Study something you're interested in (or in my case, something you can use as a backup), and while you're at Uni fire off pieces to as many editors as possible and keep at it until they commission you some work.
Case in point - I'm studying a Commerce degree (Accounting/Finance) but have been a freelance technology journalist since I was about 13. The IT journo community is fairly small, so in that time (5-6 yrs) i've had the opportunity to write for most major technology publications, as well as newspapers such as SMH. I'm taking up a full-time journo job (w/ part-time study in the evenings) in January.
Find a niche, get your foot in the door, and then if you're good you'll have the opportunity to expand into other subject areas that you might find more interesting soon enough. Personally, I want to get into business journalism once I finish my degree.