As I recall, a recent(in the last week) front-page article written by GBHill, he lays out Sprint's Network plan/vision for the coming years, it's future with WIMAX, the soon coming LTE, and its ongoing expansion with the CDMA 3G Rev A/0 network(formally known to me as the "Now Network", but it's more like the "?Where-Network?" lately ;-) ...Now, in this article, I think it explicitly states that Sprint now plans to keep selling its entire crop of 4G phones well into 2012. In fact, I could swear it specifically names the OG EVO 4G, and the OG Epic 4G. So the Epic might remain a relevant phone to the marketplace for a while longer.
And besides, even if the Epic 4G actually DOES get pushed out of it's faded spotlight 2 minutes from now, it is still very much a powerful phone, with a GPU sent from the Gods. Relevance in the marketplace comes and goes quickly, but relevance to one's personal life and unique needs can remain for much, much longer.