Gravel bikes - a new trend?

I have been reading some Interbike reports recently and apparently, this year the hottest thing is the arrival of gravel bikes. To be honest, gravel bikes did not just came out of nowhere at this year's Interbike. Some companies noticed this newest trend a while ago and introduced dedicated gravel bikes, such as Salsa Vaya.

Salsa Vaya 2 - one of the first dedicated gravel bikes? (Source: SalsaCycles.com)

 

But until now, this "next big thing" was ignored completely by the biggest manufacturers. This Interbike showed that gravel bikes may be the next fixie thing - a trend that is about to stick around for a a while. That's good. While the fixie fashion was in my opinion just plain silly (I would never recommend a brakeless fixie bike for city riding.), gravel bikes are clearly very different animals. Or are they?

 

I am trying to understand what a gravel bike really is. It seems to be a mix of a cyclocross bike, touring bike, 29er MTB and probably something else. From what I figured out so far, a gravel bike is essentially a cyclocross bike but with a slightly relaxed geometry (longer chainstays, slacker head tube angle), clearance for slightly wider tires on 700c wheels and often - disc brakes. All this makes it very similar to a 29er MTB, but on a bit lighter side. It just seems to me that manufacturers smelled a new, tiny market niche and will try to persuade us that we need just one more bike.

 

I guess, all this means that we can probably call those bikes we already own, gravel bikes as well. Have a road bike? Put the widest tires your frame can handle and you can likely call it a "gravel bike". Have a 29er? Use skinnier tires, about 40mm wide and swap handlebars to drop bars. Have a touring bike? Just remove all that touring junk (racks, fenders, etc.), put wider tires on and you have a "gravel bike". Have a cyclocross bike? You're pretty much all set, just replace those knobby mud tires with something more suitable for dry conditions.

 

Interestingly, over the last few years I have been slowly converting my old Lemond Poprad into a gravel bike - not knowing about it! First, I replaced brakes and handlebars, then wheels and tires, and finally the crankset. All these modifications made my bike more off-road friendly and suitable for the conditions I like riding in the most. Now I know how to call them - gravel grinding.

Am I right or am I completely missing the point? Are gravel bikes something entirely new that didn't exist before?