Ok, right now there's a huge discussion going on in http://bitcointalk.org/index.php?topic=2162.0
and I would support the changes to accepting only standard transaction would it not disallow exactly what I've been looking for: the ability to reuse a BC Address for multiple transaction and being able to distinguish their purpose.
Admittedly it's a hack, but a rather clever one, it was possible to insert a comment to a transaction followed by an OP_DROP which would remove it when checking the TX on the clients.
Why would one do this? Right from the terminology it's clearer, I wouldn't create a new bank account just to receive a single payment from someone, what I'd do is give him a payment slip, with a reference ID, and I'd later check if I have received a transaction with that ID.
And for the more practical minded people, it's safer! Why? Because if you generate a new address for each transaction, and you then loose the wallet, but have an old backup, in which the new keypairs aren't, you will be able to recover the Coins that you have received for keypairs in your wallet but the new ones will be lost forever.
You see it's rather more logical to separate transactions and accounts (as the new name suggests for addresses).
I therefore put it to a vote to include an official means to add a reference ID into transaction should one be supplied. To keep it simple and to keep the block chain small we could agree on allowing UUIDs in their 16 byte representation as IDs.