How sure are we that the file name isn't just for someone's dialogue -about- the snow prince? Perhaps this guy, who believes himself partly related to the ancient falmer, will return? http://www.uesp.net/wiki/Bloodmoon:Athellor
I was thinking the same to be honest.
It's probably just a bunch of dialogue similar to the story Enthir from the college of Winterhold told us during the thieves guild questline.
Don't get me wrong, I'd really like to see decent Falmer DLC, it's actually the one thing I really want to see, but it'd be too good to be true. Bethesda went out of their way to portray the Falmer as hostile creatures who are too far gone to ever be redeemed.
And if it isn't just a bunch of dialogue, this here:
Animations
DLC01Chair_SnowElfPrinceFireBall.HKX
and this one:
Animations[b]DLC01SnowElfPrinceAscensionBurning.HKX
make me suspect, that we have to attack the Falmer or the Falmer attacks us.
I wouldn't put it past Bethesda at this point, if they make us kill Falmer
again instead of giving us an interesting storyline involving them.
Some NPC will probably ask us to go to Blackreach and the Snow Prince in a chair is actually the high level Falmer who was perched on that throne like chair in the city down there. We kill him, loot an item and report back to the NPC, who thanks us repeatedly for saving the day, quest over. I could really see that happening.