What do you do when your internet connection is broken and you have to blog the Genre of the Week from a public library computer with no sound in twenty minutes? You inevitably pick a genre that's brief enough to match the time. And that, bascially, will have to be a one-band genre.
Now, bands who try to name their own genre have always existed and some have been successful where others have failed. For instance, I see real possibilities for Bongo bhangra to succeed as there's no better way to describe the music coming out of Tanzanias indian community. Whereas "softgrass" (which I spotted off TV the other day) is just a vanity name for country pop.
Eurocrunk you can't be certain about. On the one hand, the american genre that gives it its name is pretty much gone, which means it should search for another name. On the other hand it seems to have established itself pretty well. Search for the term on Youtube and you get 28 different videos which is a decent start, and not all of them by french artists either! Plus it has a comprehensive last.fm page and a (small) french wikipedia entry.
Not so bad for a genre created a couple of years ago by a very small Swedish hip-hop band - Stacs of Stamina coined the term back in 2003. Since then it's spread to mostly the francophone world, where the band has many connections. To be perfectly honest, at this point there is little more to eurocrunk than a subset of the dirtiest dance sounds mixed with conbtemporary american hip-hop, but hey, what great genres haven't started out that way?