In case you don't subscribe to the bitcoin-development mailing list, we've been talking about a new BIP:
"Bitcoin blocks and transactions are versioned binary structures. Both currently use version 1. This BIP introduces an upgrade path for versioned transactions and blocks. A unique value is added to newly produced coinbase transactions, and blocks are updated to version 2."
Full BIP: https://en.bitcoin.it/wiki/BIP_0034
Mailing list discussion: http://sourceforge.net/mailarchive/message.php?msg_id=29505990
Pull request that implements BIP 34: https://github.com/bitcoin/bitcoin/pull/1526
BIP16 "Lessons learned" : https://gist.github.com/2355445
I'd like to keep most discussion on the bitcoin-development mailing and not here on the forums, although I do plan on posting to one of the mining boards to warn solo miners and pool operators that they will eventually need to upgrade (I expect it will take at least a year and probably two or more for 95% of hashing power to upgrade, which is the proposed timeframe for full BIP 34 support).