I can't imagine what if any extreme improvements Apple will be able to throw at the MacBook Pro line up. Updated processors, great ram capability, maybe squeeze a better battery into it. The shape won't change or the screen.
I think between now and August the biggest updates will come in the shape of iWatch (maybe), iPad Pro (which might kill the MBAir), Updated iPad internals, iPhone 6 (highly doubt), Updated Thunderbolt Display (they'd better update it or suffer) and who knows what else. But I think this is a good list of maybes.
Point being, if you're high and dry now then pick a computer up, you won't regret it. But in this system items are always being made to "be better" so you'll only be winning until the next big thing comes out. Like you said, you've never had a Mac before, it might be worth it to pick one up earlier so that you know you even want a Macbook at all. OSX isn't hard to navigate but being efficient with a tool means know how it works.
0.02$ from a college student who was in the same situation.