I was just reading a report of a speech given at SMX Advanced in Seattle where the speaker, Matt Cutts, stated that NoFollow links no longer conserve page rank but that they in some cases the evaporate it. The example given was as follows.
You have Pagerank of 10 and that page has 10 links on it. 5 of the links are NoFollow. At this point the belief was that the remaining 5 links would get a PageRank of 2. Cutts stated that the while the NoFollow links would pass no Page Rank, the remaining 5 links will only get a PageRank of 1.
I am not certain if any one else had seen this but I wanted to post it just in case.