I just reached the rank cap in Halo Reach today. I am happy to find out that my credits are still secretly going towards my next rank, although I won't see it until the cap is raised. I would have been a little bummed if all I was doing was increasing my bank account, haha, although that isn't such a bad thing with how expensive some items are. I look forward to the communal efforts to lift the cap. If it happens soon though, I can safely say I won't be skipping over any ranks.