I've been testing this out for some time, patch applies cleanly (except for version.php - which is normal), along with most recent patch in MDL-16036 (lib/weblib.php).
It's working mostly fine for me, though I have a long list of warning and one fatal error in blog/lib.php .. the problem seem to be in lines 784/786, as "array" appears in the sql statement. I got there (/blog/index.php?postid=1) by clicking on "full entry" from the assignment grading screen (but I got there from some other link yesterday).
Some code formatting needs to be fixed (all "if" statement need to have { and }, event for one-liners), to follow the Moodle rules.
I couldn't find out how blogs associated to forum work. Didn't spend too much time on that though. I suppose we are at the point where writing some basic (end-user) documentation about how to use this patch would be good.
I wish the blog_fetch_entries_sql function (the previous bug seems to come from there) could be somewhat cleaned up. I know most of this has been part of Moodle for a really long time ... but if all this query building could be simplified (and use placeholders), it would look a lot better. Separate issue, I guess...
This patch contains all of my work so far. It is based off the current CVS snapshot.