I can't help being a bit worried about this. I have a number of concerns:
- Will this result in Microsoft buying out WordPress?
- Could the extra users make WordPress more attractive for others to buy out?
- Will WordPress continue to be an open-source independent platform?
- Can WordPress maintain the same level of support with al these new users?
- Will the extra users mean that WordPress.com becomes a more attractive target for spammers and hackers?
- Will the ex liveJournal users result in a dumbing down of the average blog, giving WordPress a "MSN" type reputation? (OK, I'm probably being a snob here, but I can't help worrying about "wordpress users" getting the reputation that "MSN users" used to have).