Twitter uses rel="me nofollow" for external user generated links. Very funny, but does it work the same way as just rel="nofollow"? If anyone has actually tested this please let me know.
I'm pretty sure this exact question appeared on DP or somewhere else like Yahoo Answers... rel="me nofollow" actually means two things; the "me" means the URL is related to you. This would be useful if you are promoting a blog of some kind as it would tell the search engine that the site is about "me" the nofollow means it shouldn't follow it, so it won't. IMO, rel="me nofollow" is worse than rel="nofollow" because I'm not going to post a URL for a website about me, my blog, or anything like that. And yes, it is just as pointless as rel="nofollow" in terms of backlinks.. you do get anchor text for it though, which can help a little.
Yes, I read the same question on an other forum but I did not understand the answer there. So "me" and "nofollow" are two different things. I see that twitter uses only nofollow on any link you post. Perhaps they do that to prevent spammers.
Its in the format to assign two different attribute values at the same time. e.g "follow index" is same as "follow, index". the attribute rel="me" is used for bi-directional links.
The me nofollow would basically tell Google you placed the link not somebody interested in the site as a credible source of something... At least, if I understand this correctly. So essentially, it's worthless.