tedster - 9:47 pm on Mar 28, 2011 (gmt 0)
More about that change from late 2007 - at that time subdomains began to be treated LESS like independent sites. See Subdomains and subdirectories [mattcutts.com] from Matt Cutts' blog.
Unfortunately, I don't have any current data on this. I also would like to hear from anyone about whether Panda losses also seem to affect their subdomains.