I think people pattern-match singularity to religion because it, essentially, promises the same things - long life / immortality, solution to many problems of humanity, superhuman beings / intelligences, etc. But this match is wrong; it doesn't matter if religions talk about the same things. It only means that those are human needs and desires. In case of singularity, there's a real chance that we could do all of this without need for supernatural powers, so it's worth discussing.
I also don't see anything religious about the concept. Religion by (etymological) definition seeks to understand or connect with ultimate source of things, whereas the singularity is A) about the future and B) says that the future is going to be impossible to predict or understand because of accelerating change. At best you might be able to argue that it's vaguely teleological, but I'm not even sure that that is correct because the theory doesn't make any real predictions for what happens in the longterm after the singularity.