There's a very good chance I'll move up to an M3 in the next couple years, although I'm still contemplating a 1M as well.
The 1 series is great considering I'm not quite married yet and have no plans for children in the near future. I've always been partial to a lot of power in a small package. And as I've stated in a previous thread, the 1er let's me say things like "she's basically a two seater". And "the backseats are tiny, you wouldn't be comfortable back there". =p