Is Gillibrand really that impressive, or are people just mentioning her because she's a female Dem. from New York state? I have to admit, of the little I've seen of her, I haven't been terribly wowed. Amy Klobuchar seems more articulate, from what I've seen of her. I agree that there's a good chance that the Dems would want to go with a woman in 2016, but if Clinton doesn't run, would Gillibrand really be the best they could come up with?
Klobuchar seems to have some heft on policy matters. Not unlike Barbara Mikulski, except she doesn't remind you of grandma. Personally, I'd love to see Klobuchar advance.
Hillary Clinton remains the leading light among Democratic women...not necessarily because she's "all that", but she's the most prominent.
Like you, I am pretty uninformed about Gillibrand. I'm not doing as good a job as I should when it comes to tracking governors, either. In either party. So far, I've admired Republican Jodi Rell of all the GOP women. But moderates don't win Republican primaries without the requisite "come to Jesus" moment on gays and abortion. Rell strikes me as very unlikely to undergo such a transformation.