You're right it's competitive, but less so now, at least in the sense it seems like most people who want Marines get it - of course the guys who suck at the PRT aren't getting it, but there doesn't seem to be anymore big surprises. They have increased the spots every year and they continue to project the Marine slots will increase. I'm Class of '10 and they think they will be taking about 300+ from my class - so just about a third of my class will be going Marines.
I should add as a caveat, to go Marines out of USNA as of now, it's almost necessary to attend Leatherneck or MAGTF after 2/C Year.
I should add as a caveat, to go Marines out of USNA as of now, it's almost necessary to attend Leatherneck or MAGTF after 2/C Year.