Depends on what you mean by "pull this off." The alpha itself is pretty beefy for the alpha's I've seen. The API isn't stable but it's certainly nothing to sniff at and the web GUI is more realized in a few weeks than twitter was in a few months (learning from others mistakes makes this easier, of course).

Dalton's pretty clear said he's "not trying to kill twitter" see, http://www.quora.com/Twitter-1/Will-app-net-kill-Twitter/ans...