I'm keeping it at first come, first served for two reasons.
1 - the person who gets last choice of team gets first pick in the draft (unless they fall asleep at the keyboard or something). I find that more than fair, seeing as how they get last choice of team.
2 - I've been in previous draft leagues where the draft takes weeks because the person who is next in terms of salary has not logged in. This method is a fair way of making sure that doesn't happen.
3 - while this isn't one of my two actual reasons, it means there will have to be some strategic drafting. If ten owners all pick Ilya Kovalchuk in a minute span, then there's a clear way to decide who gets him (the first post that actually gets registered). It means you'll have to have several backup options in mind, in case someone has beaten you to the draw.