Well, what I've noticed of late is that Marvel is not only hyping X-23 but all of their new characters in an attempt to have new characters fit into the complicated folds of the Marvel Universe. As we all know this is a tough feat and characters have certainly fallen victim to not living up to be as good a character as they already have and Joe Q's been taking note of this too, it seems... What they are really trying to do is expand so that they can have people grow up with these characters like a lot of people grew up with Spider-Man and the like... You really can't blame them, you know?
If X-23 showed up in the Ultimate Universe and had her own origin mini, yes I'd probably pick it up. She seems interesting to me and she really does have potential to be Marvel's next big thing.