Truthfully...and this can rest heavily with one's own opinion on technique...it not really a useful practice unless your doing a really big IPA. The longer the hops reside in the boil, the more of the delicate (volatile) oils get boiled off resulting in just residual bitterness rather than the floral or fruity aromas that some imperial IPA's have. First wort hopping works great when your doing a really long, say a 75-120 minute boil, on a batch of wort and your looking to impart a large amount of bitterness.
Your going to have a lot of hop additions throughout (with a long boil, for example) most likely with a majority of the early additions contributing to a large percentage of your IBU's (sort of the name of the game with big IPA's, nor entirely, but sort of). So, by adding the hops early-you give the hops more time to impart that notorious bitterness hops are known for thus...higher IBU's.
So to answer your question, it depends on your recipe and what your trying to achieve. The gentlemen about mentioned doing it on an amber ale which is for example unusual but still AWESOME! It's great to experiment and that's the fun with home brewing! Try it and see what happens!