Something that makes you be a good all around rider. Be able to climb to the top of the mountain, take on gnarly descents and drops while flying downhill, and be able to do tight steep singletrack, whether it is up or down. Also be able to do at least 15miles of riding.
5+" of travel
Less walking, more jumps and drops
Not being a weight weenie about bike or components
To me it's a long-travel trailbike (5-6" both ends) that has an effecient enough rear suspension design or shock to allow it to be pedalled through most uphill sections of any trail; beefy enough to withstand aggressive riding down hill; and with little or no chain-growth issues so that you can confidently run three rings and a front derailleur without worrying about dropping the chain due to suspension movement when the going gets really rough and fast.
What I'll do when I get too lazy to train anymore.
All Mountain is just what Gastro said.
Like a circus monkey on a stolen Harley......
A bike that lets you ride to the top then strap on your gnarboots.
Cross country that is actually fun.
elf 232 contra mundum.
Longer travel XC bike plain and simple.
Santa Cruz Tall Boy
Cannondale CAAD 8
I think "All Mountain" refers to a type of bike(marketing bs that has apparently worked quite well) not a riding style.
I've ridden my DH bike for my 30km one way commute to/from work and for multiple hour trail rides (along with using it for it's intended purpose), I've ridden my road bike on singletrack (again along with using it for it's intended purpose), and I've used my Blur 4x for shuttle trails, commuting, and trail riding...so...do these marketing terms actually matter?
Just ride the bike that best suits your trails and your riding style.
I'm not quite sure it's fair to characterize it all as marketing BS. I think the perversion by marketers of the term to include bikes in the category that do not belong has muddied it possibly to the point of uselessness.
But by its nature, marketing has to try to say the most with the least amount of words to get a clear point across. Advertising space, be it electronic or print, is costly and your audience's attention span is short; so you need to get the most impact out of the shortest amount of time, space and words.
So marketers glom onto catch-phrases that they feel best get their point across with the fewest words possible. Where it might be more descriptive to say "This is a 5½"-travel do-it-all trail bike that climbs like a goat, descends like a banshee and leaps boulders like a gazelle," it's much more direct to say "It's an all-mountain bomb."
marketing term used to sell $2,500 bikes to people who only need a good $1,000 hardtail.
To me it appears as a tough XC bike capable of all terrains.