I'm fine with dividing drow, but I really don't like the way they went about it. Like I wrote elsewhere - something like "surface drow" and "Underdark drow" would be better. Now we only have two very specific options conflated with worship of certain gods. Plenty of drow characters wouldn't fit well with either.
And generally I don't mind separating drow from other elves - they are more distinct than most other subraces. I'd do the same for duergar (maybe not subraces), but not for svirfneblin, who are more like their surface cousins. There's also the matter of dialogue options, like Zarna said; a surface drow ("Seldarine") and a "drow society" drow ("Lolth-sworn") will have different knowledge etc.
