Almost all of the video sharing sites (i.e. - Youtube) have the the NoFollow attribute in place for outbound links. As far as link building, it won't help much directly from those kinds of sites.
There are other sites that take (steal) the content from these video sharing sites and reproduce it. Many times these have DoFollow links. It's hard to say if it would be worthwhile as many of these kinds of sites come and go, and have little to no authority.
As far as the automated voice to make videos, they are very boring, and obviously created by a computer. No human would listen/watch them. In my opinion it is video spam.
Now if you could get someone to read the articles and put them into the videos, and match them with your own images, then you might have something (assuming that the article is worth reading in the first place).
I think the automated videos concept is a good idea, but with the current technology, it only produce terrible videos, that really no one wants to see (and the video sites don't really want clogging up their sites either).