No they don't. Just because they show the link in Yahoo Site Explorer, does not mean they apply any weight to the link. Yahoo shows all links there, nofollow and dofollow, and any other crap link they can find. They do not even bother filtering out multiple Urls that point to the same page content in a lot of cases.
This is something I didn't know. I always assumed that how many backlinks you have in Yahoo somehow influences your SERPs (at least in Yahoo). Does this mean that all nofollow links are absolutely useless in terms of SEO? If that's the case, it means all those people that comment on blogs with hopes of getting a backlink are really wasting their time.
There is no weight given to a NoFollow link in Yahoo (or Google for that matter). The nofollow link has no SERP value. Per Yahoo! Search Help concerning Nofollow and Slurp: A keen observer of this help document will see that nofollow links ARE good for one thing at Yahoo, they will follow the link to the other side and index the content.
Using our names is good but i have seen many guys those use their domain name in that place , so they can get backlink from that .