Haven't seen this posted anywhere yet. Seems like SlingPlayer may indeed be coming to the iPhone (or at least submitted to apple).
http://www.slingcommunity.com/blog/entry/32664/Sling-Media-Hopes-for-Q1-Release-of-iPhone-SlingPlayer/
http://www.slingcommunity.com/blog/entry/32664/Sling-Media-Hopes-for-Q1-Release-of-iPhone-SlingPlayer/