You're the guy who rides road, right? For years, Specialized's flagship road bike was the Allez. Suddenly, they decide to go carbon fiber, and instead of making a carbon Allez, they introduce the Tarmac, and now you can't get an Allez with better than 105 components. If you want a Specialized mountain bike, you choose between the "Enduro SL Comp" or "S-Works Enduro SL Carbon." But if you want a Specialized road bike, you choose between the "Allez Elite" and "S-Works Tarmac," but you can't buy an "S-Works Allez Carbon." Why? Same reason LX was renamed SLX...marketing.
What was the old touring group? This is half backwards! LX has been around for such a long time! If you're going to add a new group, why not let the new group be the touring group and have LX be the mtn bike group (like it was in the past 20 years!).
There you go thinking logically.
Obviously, you will never get hired into a marketing job.
Okay, I could be wrong on this, so someone correct me if I am.
I believe that when SLX was first introduced, Shimano wanted to make it look like a step up from LX, fitting in between LX and XT. It was lighter than LX and supposedly better. So when LX was slowly phased out as a mountain bike groupset, people currently running LX were made to feel like they had a groupset that was inferior to SLX. I'm kind of out of the road loop, but didn't Shimano pull this same stuff with Ultegra and Ultegra SL?
Giant XTC Team Custom XC bike, Nashbar tourer custom commuter
The Surly LHT is exactly that... relaxed geometry, maximum rack and trailer mounts, sturdy frames which tend to weigh a lot (for a road bike) but which are very functional. A sort of cyclocross sized tire with fewer knobs and stuff like MTB hubs for added strength but at the expense of the road weight watching.
LX is still there and still looks like MTB equipment, but they're trying to aim it at a different market. Odds are, it will perform quite similarly, and I would say is still a step up from deore in any mountain biking situation (not like they're making it weaker/lighter to go towards a road group).
In all honestly, just like in road groups mountain bike groups vary only slightly with each model. Sometimes they get upgraded technologies, but generally the higher end parts just have more Ti and carbon in them.... sometimes they are more durable as well. The difference between LX, SLX, and XT is there, but it's by no means pronounced. Using them for cyclocross could be an issue in a few cases (rear hub spacing for example) but would technically be fine. That being said, if you're racing cross you probably don't want the extra weight over your shoulder when you run half that last lap.
I've got a hone crankset on a hardtail XC bike and will be putting 700c rims laced to XT hubs on my new commuter/tourer build (with a track crankset no less). The difference is small and of personal preference, unless you are going to strictly stay to downhill or road racing, which it seems that you aren't, there's no reason to go with one specific group.
BTW, jenson has been selling the saint RD for a while too at drastically slashed prices. I'd pick one up if I could find the damn saint rear hub..... but they seem to be in short supply. I think the saint and hone lines are both somewhat discontinued.