He was not impressive in 14' and injured in 15'. He was solid in 2013. He had glimpses of good play in 15', and we have ALOT of needs: DT, DE, OG, C, S, CB…so its reasonable to say well for now…we don't know if we can fill every need we would ideally like to…
That said, is Foster resigned yet? If not, once he officially resigns, then I could see Riley being cut.
I think a similar situation is happening with Culliver. Once we resign Blackmon, Culliver will then need to be cut or re-negotiate.