Before I used to like the way the conferences are set up, but now I'm starting to agree that single table is the way to go. We'll have 16 teams in 2010 and it wouldn't surprise me in the least if the league decides to opt for a change in format. By the time we see 20 teams, I'm sure it would be absolutely essential for proper scheduling.
We can still have the MLS Cup tourney, as well. The teams just wouldn't be divided by conferences and wildcards. Simply make it so the top 8 teams in the single table enter and compete accordingly.