^^ Can confirm that keg hopping is great - for really hoppy beers I like to dry hop in the fermenter AND keg hop with a new lot.
Some things to watch out and be aware of. Use a hop bag, or tea ball... hop trub will settle out and just continually get sucked up the dip tube, which can cause grassyness and make your beer have floaties etc..
Also, you should suspend the bag (or ball) in the keg via some fishing line, or dental floss. I've found that if you do not do this that the bag will get stuck on the end of the dip tube and block your flow. Also, if the hopping rate is starting to get grassy, you may want to remove the bag, this way it's easy to retrieve. \
Opening a keg can oxidise your beer (even slightly is bad for hoppy beers), also hop aroma will escape at a pretty quick rate with the lid open. the best way I've found is to suspend the bag about 1/3 of the way into the keg, this way it's getting a week or so of full saturation and then the bag is automatically removed as you drink the beer.