I got to thinking about all of the different types of IPA that you can get from craft breweries. It started off with American IPA and English IPA. Then came Double/Imperial IPA. Then in the last 10 years or so there has been an explosion of subcategories of IPA including: Triple IPA, Red, Black and White IPA, IPL, Session IPA, and I am sure there are a few others that I can't think of off the top of my head.
Truthfully, I love IPA and it doesn't bother me to hear craft brewers using these new terms to get another IPA out there. Why are they doing it? IPA is the fastest growing craft beer style. So why do they call a beer "Black IPA" instead of "American Black ale" or "Session IPA" instead of "Extra hoppy American Pale Ale"? Because IPA is what is selling the best. Craft brewers love to make beer, but they have to sell it. Homebrewers just get to do the making part. Successful marketing is a huge part of a successful craft beer business, and having a new IPA is what is popular right now. So really, the definition of IPA has changed. IPA doesn't actually mean "India Pale Ale" anymore. It just means "IPA" - which is shorthand for a beer that is extra hoppy.
For all of us beer nerds who have dog-eared copies of Mitch Steele's IPA book and have made historical IPA recipes (I am one of them), there are 10 more young craft beer drinkers who are just getting introduced to beer. For them, IPA is a flavorful new thing that tastes nothing like Coors Light. They can go into a bar or a brewpub or the grocery store and find an IPA and know that it is going to be different and exciting to drink. Sierra Nevada Pale Ale and Black Butte Porter were the beers that got me into craft beer 20 years ago, and IPA is what is getting new beer drinkers into craft beer now.