First, the purpose of my new page at http://bitcoinaddress.com
is to create a master directory of public bitcoin addresses of people and organizations which accept donations via bitcoin.
This is a bad idea.
Agreed. For many reasons.
Maybe it makes sense to keep a list of organisations which accept bitcoin donations. But such a list should consist in organisation names and website links. Nothing more, and certainly not the actual bitcoin addresses.
For the purpose of accepting a donation, why is this a bad idea? Since it is a donation, the organization doesn't need to know who it came from.
It isn't like your address is secret, right? If I give you a Bitcoin address, and you then do send to that address, I now know what your Bitcoin address is.
Additionally, because that data has value, the recipient will likely store it in a database. Then let's say the recipient's server gets hacked and that stored data with your Bitcoin address tied to your name winds up on some publicly shared torrent data file. What's the risk?
Won't the payment processors, retailers, etc. do the same with Bitcoin that they do with credit card transaction data? Once Bitcoin reaches visibility of higher levels of organizations, anonymity (for the average Bitcoin consumer) will be gone in 5, 4, 3, 2, ...
Fortunately, if I wish, I can create another wallet with a separate Bitcoin address, fairly easily.