How does a recipient know they can satisfy the transaction script to spend their bitcoins? The wiki page on the transaction script says:


  The party who originally sent the Bitcoins now being spent, dictates the script operations that will occur last in order to release them for use in another transaction


How does a recipient know they can spend the bitcoins they received? Would it be possible for a malicious user to create a script that the recipient could not use to spend the bitcoins, without them being aware of it? (Possibly due to a client UI limitation?)

The situation I'm describing would probably be unusual, as it would involve the sender deliberately sacrificing (and destroying in the process) bitcoins purely to spite the another party. Even still, is it possible, and what measures (could) protect against it?
I don't think your threat model makes sense. If you "send me Bitcoins I can't claim", you've done the equivalent of nothing at all, except you've wasted some of your own Bitcoins in the process.

Currently, clients will only recognize Bitcoins as being sent to them if they can confirm they can claim them. Non-standard transactions (those with scripts other than the two well-understood forms) are ignored.