This is more of a surprise than Authoria (last post before this). Kenexa was voted the top RPO. While I'm not sure who the competition was, I'm betting it includes the likes of Brassring and Recruitmax. Kenexa has not (to me) shown a great depth in product functionality, breadth in their product suite, or the marketing capability and penetration into the Fortune 1000 as Authoria has. I think other vendors have put all the components of Talent Management better than Kenexa has.
My top picks for Talent Management suites are still Recruitmax and Authoria.