I can't speak to whether or not Panda is penalizing profile links, but my experience shows that they don't hold much (if any) SEO value. I gave up on them quite a while back unless the domains and discussions are relevant to my niches.

I did notice two interesting bullets in today's "40 Changes for February" article. The first was their admittance that they "turned off" a method of link analysis that they've used for several years. The second was the "Spam update".

I couldn't help but think the first was related to the devaluation of some characteristic of low-quality links like blog comments or forum links. As to the "Spam update", I had a gut-wrenching suspicion that this may tie back to their recent improved detection of HPBL networks. Obviously, these are just my thoughts and I have no data to validate them.

Profile links and any other kind of links don't generally get you penalized. At least not much. As you noted, Google Bowling would mean that Google can't possibly figure out who is doing this.

I get great results with small amounts of profile backlinks that I create and then get literally thousands of internal backlinks from each forum to the profile. It makes the profile look active on the forum and that many backlinks to one page means the backlinks is worth a lot more. Just creating them and pinging them does nothing anymore in my experience.