Slush is not far behind. However I am in a quandary as to which pool to stick with in the near term. Slush only takes 2% and Tycho takes 3%, but the difference from long polling and invalids has been no more than 0.5%, so over time payout is slightly better with Slush. Pretty miniscule overall. Scoring on Slush is a slight disadvantage due to the need to shut down miners for small periods of time (my 6970 hangs when I try to watch any internet browser embedded video) which means accidental browsing to a page with a video on it (most news sites) will hang my computer, so I need to shut down the miner for some types of web browsing. Advantage deepbit until slush implements long polling.
Also, I am a little worried about what was announced for BTCMine that closed down new registration. Where are the reassurances that this can't happen in the two largest pools (potentially undetected). Having said that, payout want doing do well when I was with them, so I left, but since I left and the announcement, the variance has definitely been in their favor. Short term I know.
In short, the future holds a lit of promise for the pool that can break out with the best combination of features, fees and security is going to win the battle.
I think BTCMine made a mistake by going to 0% and relying upon donations (I think they will eventually shut down with that move).
I change my mind about BTCMine's decision to block open registration. They did implement a method for automatic donation and that changes my perspective on their decision greatly. I have more hardware online (provided the main board is intact ... waiting on new PSU) and feel they may be the best choice available to me ... I need to give it some time similar to what I have given Slush and Deepbit.
I think the market drop may be a combination of the closing of PayPal with Coinpal and the fear that the same thing will happen to Mtgox. The need for a new exchange to cash is a great opportunity, but until then, there will be some depression knowing that it may be difficult to get bitcoins exchanged. Also, I think that the reason for BTCMine closing registration may be valid and potentially systemic in the pools. I hope not, but I don't like the odds after all the sudden profit taking. Tycho and Slush, please watch your pools.