Is there any kind of port blocking planned/implemented?

Yes and no.
Some ports will be blocked for security reasons (25 outgoing and so forth) per international practices. Things like Bittorrent and DC++ will work fine and are not blocked or shaped at present.
We're implementing a large P2P cache, and we're even experimenting with running a private torrent tracker for Hayai customers only (this way you can be sure that you are only using "Hayai Zone" bandwidth).