- You can't stream live TV right now, but I've been told it's planned.
- I assume you mean the TV guide when you say programming grid. I don't know, but this point doesn't really matter due to the first answer.
- You can supposedly record and delete programs from a client, but I haven't done it yet.
If you get HDHomeRun tuners, you mitigate the only limitation for this setup right now. The drawback is you have to set the tuners up on each individual machine. This will automatically solve the TV Guide issue because each computer will have its own after you set up the tuners properly.