Uh, I'm sure there are lots of players who would use that.
A lot of bigger and more established LSs already have their own webpage, and this was actually a problem with FFXI, in that you almost had to have one in order to run a really clean shell (at least it really helped to improve communications in an organization that is based... entirely on your communications). The problem of course was that there were too few people willing to actually keep up a webpage for their LS, and especially when you're just starting out, there's not always a lot of incentive for people to actually go out of their way to check the webpage.
So yes, if you provide a service for free (or even for a very low cost to one person/premium bundled) that will allow people the primary benefits of having their own webpage while not even having to leave one of their most-used resources for the game (the alla site), I think they would probably use that.
It may be too late for a FFXI feature to get much use just because such a large percentage of the remaining playerbase already have their own webpages and community. But with either group (XI/XIV) it would at least be useful for LSs that are starting out or in transition as they're moving to their own domain.
It's probably clear from my language that I already have a pretty solid LS in XI that I hope will carry over to XIV, and we have our own webpage with lots of great features. Having said that, it's unknown at this point if we'll have a cross-game guild, or if we'll have two separate sites, or if the people who operate the site or the LS leader will even play XIV at all. So when XIV rolls around, even our established LS could end up using a feature like that, if only temporarily.
But there's also a possibility that ingame features in XIV will absolve most of the need for that kind of cohesiveness. Really it's just a matter of cost-effectiveness for you guys, and a bit of a gamble in the demand that the game itself creates.
Ok, now we're going to get slash fiction of Wint x Kachi somehere... rule 34 and all...
Never confuse your inference as the listener for an implication of the speaker.
Good games are subjective like good food is subjective. You're not going to seriously tell me that there's not a psychological basis for why pizza is great and lutefisk is revolting. The thing about subjectivity is that, as subjects go, humans actually have a great deal in common.