As someone who has played nothing other than a Rogue for 4 years, when I first heard about the Thief having an AoE blind a few months back I crapped my pants with OMGOP. Then I hit the wiki and found out that Guild Wars blind and WoW blind are very different things.
I, on the other hand have been playing LoL exclusively for so long auto-assumed blind meant a short duration debuff that made you miss all attacks. I had to really stop and remember what blind was in WoW. lol
Thief seems to be a GW assassin with some limited stealth and mandatory ranged for ranged viability. The speciality is still directly derived from assassin - superior positioning ability via complex shadow stepping mechanics.