I am actually more excited about this then the Affleck Batman movie. Whedon has done wonders with Buffy and I am sure he will do it here too.
Personally I would rather see an Oracle movie. Something akin to Birds of Prey. Although given Batman’s age in this new DC Movie Universe Batgirl would be Oracle with being Batgirl a near distant memory.
Of course Yvonne Craig will always be the Batgirl standard. I kind of which they use the outfit. Although it seems impractical.