Navy = a job
USMC = a career
That said, if you expect to be a Navy pilot, you best plan on majoring in engineering or physics and taking 5 years to get your degree. If you go USMC and major in anything that starts with "B.S." you can graduate in 4 years. Truth is that USN expects pilots to understand higher math to a functional degree,, while the USMC expects pilots to be only able to spell "math". The USAF expects pilots to be able to teach higher mathmatics to people like Hawking, Heisenberg, and Einstein; even if they are dead. 
I somewhat agree, I think the Navy holds their pilots to a higher degree than the USMC on a few levels for essentialy the same thing in the end when ya boil it down. However I've known two Navy pilots (one rotary, the other F-18 (until after all that training he and the Navy figured out that after a couple weeks at sea he gets huge long-term sea-sickness,

even on something as big as a carrier) and ultimatley mutli-engine) and one USMC pilot (rotary: blackhawks, cobras and heuies when he started). After they finished up with their active duty the two Navy pilots had a job signed up before they got out (One flying Fed-Ex cargos, the other for a private firm that is usually contracted to work for power utilities), but my Marine budy only gets to fly these days in the reserve (he's always been looking though, ended up falling back on his EMT training he got in the millitary and his dad helped him get a job in the LA City FD pdq as an EMT when he got outa the service and found himself without a job to support him, his wife and newborn). He has however been on the FDs list for their helicopters and pilot openings, I think he's finaly getting a break after waiting this long and starting some training this summer to begin certification (still up in the air if he'll ever get a spot, but it's hope and he's working hard for it).
So while I agree that hte Navy expects and demands more from their pilots, I think in the end it might pay off because potential employers know this too.
(I also come from a proud Navy family, so if I had to nudge ya in one firection or the other... but the Marines are still an excellent choice

)