Google Matt Cutts: 301 Redirects Dilute PageRank Equally To Normal Links
The reality is, they don’t pass full PageRank but neither does normal links, which we knew. The problem was most folks felt that 301 redirects pass minimum PageRank than normal links and that is not correct.
Matt posted a video and saying:
The amount of PageRank that dissipates through a 301 is currently identical to the amount of PageRank that dissipates through a link.So at present, there is no difference between a 301 and a link in terms of PageRank dilution.
Therefore, if you have many redirects, like chains of them from one url to yet another to another, that is a called bad thing. Yet one or so won't damage you.
Here is Matt's video:
This is obviously one of the specific topics that is pretty cut and dry yet once you start to ask additionally questions, with more variables in the mix, it can become a "what if" type of scenario that is not so drop and dry. As a result we had the misunderstandings in the first place, because Matt did not want to lead folks on the first time - I suppose?