BurtW, thanks for the informative replies!  You state that using any address (be it a vanity address or a randomly generated one) multiple times poses privacy risks.  What's your stance on mining in pools?  Some pools (Eligius, p2pool, etc) use a BTC address as your worker name, and pay directly to that address as part of the generation transaction.  Other pools (GHash, BTCGuild, etc) use a wallet address that you provide to send you payouts.

I mean, I suppose if I were entirely paranoid, every time a block was found or a payment was made I could reset my miners/pools to use different addresses, but that seems a bit like setting up a faraday cage in my basement and wearing a tin foil hat