When I was choosing a bike, it came down to either a Surly Crosscheck or a Surly Long Haul Trucker. Ultimately I picked the LHT because I liked the color better (rich blue versus poop brown, hmm...) and I really like the name "Long Haul Trucker."

slcbob is right, the categories define broad generalities but don't really describe a bike accurately. My previous bike was a Jamis Aurora - it was considerably lighter than the Surly, had more aggressive frame angles and a shorter wheelbase for more responsive steering, and overall was quite a bit more sport-oriented. Despite being billed as a touring bike, it was probably lighter and more nimble than the Crosscheck. Because of the nimbleness, it's also probably not the bike I'd choose for riding across the country, which the LHT is with its slack angles and stable handling.

If you want a bike that's pleasant to ride, that you'll enjoy riding for years, and that'll keep you looking forward to work on Monday just because it means riding there, then test ride a bunch of bikes and buy the one you fall in love with.