For next year at least, you're going to have E-Rod figghting for pitching time in the bottom of the rotation, if Price, Porcello and Sale are all healthy. That's 4 guys for 2 slots, 3 guys for 1 slot if you lock E-Rod in as the #4, and if the minor leagues turn up another bottom of the rotation guy you should be OK.
That doesn't mean our depth won't be tested, or that more depth isn't nearly always better, but the idea that there's no home grown guys to come in and take a rotation spot is simply untrue.
Personally I think Brian Johnson has earned a good honest chance at a rotation spot next year. If he doesn't get it because the depth ahead of him is too good, that's one thing, but he definitely looks like he's starting to round into shape as a solid #4 starter. He'll be in the wings and so will Wright at the start of the year, so with those two fighting for a job and Velazquez in the bullpen it'll take some injuries to really start to fray our depth.
Speaking of the minor leagues turning up another depth arm -- I won't guarantee anything, but keep an eye on Mike Shawaryn next year. He's not an ace type, but he's got some potential as another depth guy.