Page rank are closely related to dofollow links. Any outgoing dofollow link from your website / forum / blog pages considered as passing page rank juice which means your are virtually page rank bleeds. “Bleeding” is a strong word to use for outgoing dofollow link. I guess it explains better now that our page rank only drops if we give out too many dofollow link out. Having a healthy type of outgoing link will always benefits you. For example, if the page you are linking will give you back trackback link that is dofollow, than it is beneficial.
Next page rank update is expected by July or August 2009. Control your outgoing links from your sidebar, posts, contests, etc especially dofollow links. Plan your link building activity to increase page rank. Concentrate more on dofollow link building. You can start with commenting on dofollow blogs. Other than that, active on dofollow forums. Personally, I’m not a big fan of link exchange method. There are plenty of ways to get one way backlinks. As for this blog, I’m bleeding at comment section which gives keyword anchored dofollow link for commentators. To counter it, I’m doing high PR dofollow link building for this blog as well.
If you give out too many link with dofollow from your website, make sure you make some quality backlink to you. If the balance is good, the page rank will not move up or down. If the page rank bleeds out more, it may drop. If the total weight of incoming dofollow backlinks exceeds outgoing links from you blog, the page rank may rise. If you still don’t understand about page rank or dofollow well, click on “Page Rank” tag on my sidebar. Who knows, you could teach someone about page rank and dofollow too.