It's been about a year for me, and it's blissful. I tried to watch some Channel 4 UK on demand, and even that small amount of advertising had my teeth on edge. It's amazing how quickly you stop calmly glazing over for the high octane mindlessness you find in advertising; the tolerance just vanishes. The music grates, the acting is more obviously terrible, and messages more obviously manipulative... when you're not constantly immersed in them.

I also find that I watch less, because I'm actively finding anything I want to watch, rather than passively channel surfing or just "seeing what's on".