few questions...

my brother and i are looking to play this...

can we both go online at the same time on the same wii?

is the offline split screen co-op the same gameplay?

Nope.
Nope.
The offline is just fighting bosses together with set gear(You don't use your own).

this makes me sad

could have used our offtopic to bump it xD

still worth getting.

you and him can have sep characters...or you can both work on the same char either way, its worth it.