Pretentiously artistic; self-important or self-indulgent, especially when describing an artistic project.
Someone who is arty-farty.
Of art or other things: appealing to the tastes of an intellectual or sophisticated (sense 1) person; cerebral; also, cultured, elegant, refined.
Of a person: having obtained worldly experience, and lacking naiveté; cosmopolitan, worldly-wise.
Complicated, especially of complex technology.