The 4 true freshmen aren't likely going anywhere (Exinor, Outten, Howard and Samuel). Out of the 3 redshirt freshmen the staff seems high on Denmark and Gonzalez, as well as the speedy Brown who reportedly is almost recovered from a serious injury. It would seem that Wallace, Evans and the two incoming transfers (Hudson and Ross) will be here, so that makes 11. I only count 5 additional WR's on scholarship, Clifford, Flowers, Ivey, Johnson and Saunders, as I believe Nastasi, Black, Cunningham and Estrella are walkons. It would seem that those last 5 on scholarship have a lot to prove in the Spring if they haven't seen the writing on the wall by then. Clifford seems to have lost his spot in the slot by the staff may want him to return as a safety net with the 105 roster limit. And Saunders has shown more than the others but will be coming back from an injury and would be competing for a backup spot in the slot at best.
And it seems that the staff will take another incoming WR transfer if a good one wants to come to PSU.
Lots of changes to be expected between now and the end of Spring practices, but with the expanded roster it's reasonable to expect at least 13-15 WR's on the roster going into next season.