Update May-2017: there has been some novel research into this, and it will be possible to tweak the sending wallet to allow sending to a special address acting as an "alias". The funds would go to the same wallet regardless of the number of these "alias" addresses used. The scheme makes it so that given an "alias" address, you can't work out the regular address or other aliases. Again, the actual records on the blockchain would never store any public address (be it regular, integrated, or alias), but the sender would generate a seemingly-random one-time destination address, as usual.
Read up on Github: https://github.com/monero-project/monero/pull/1753
I will attempt to answer the question while considering what had been discussed through other channels: Reddit, IRC/Slack Pt.1 & Pt.2