Earlier Squidoo lenses were in SERPS but when webmasters started misusing it... Google slapped it. Ezine Articles is a bit better interms of rankings and backlinks.
yes squidoo is dofollow lens we can get dofollow backlink from there but i don't think we can get much traffic from there so don't waste your time just create links for backlink that is sufficient for all
I am fairly sure that Squidoo links in lenses are follow not nofollow links. As for how well they provide traffic to me it is like any other traffic generation tool, the more you put into it the more you get out. You have to take your time when creating your Squidoo Lenses. You have to select the best keywords to use in your Lense, the correct tags for the Lense, then you have to also promote the Lense as priviously stated. However I created a Lense and in a matter of a few days it had rank very well in it catagory and I started seeing traffic small amounts of course each week. The longer it is out there the more traffic it will soone generate.
squidoo lenses are good for SERPS; i believe ezine articles and hubpages are also good and helps in terms of ranking