I believe Snoop and Dragtastic are both correct.
People will never grab EVERY possible 1-worder in dot tv, especially when Verisign is re-pricing TV drops at some incredibly outrageous prices like alive.tv @ $4500, or jungle.tv @ $1800, etc.
But the best 1-worders that make sense and work perfectly with .tv that are reg fee, are definitely all gone now.
Sure there are a bunch of 1-word reg fee .tv's left, but they don't make too much sense for development, IMO
Let's re-phrase your question though...
"How long will it be until all decent/normal-language 1-word .tv reg fee domains are registered?"
I have thought about this quite a bit.
Since most great .tv 2-word domains are mostly gone now, I honestly believe that by the end of 2011, you won't be able to find any 1-word reg fee .tv's at all