looked into sao a little bit
looks pretty fun
reminded me of phantasy star

u got me interested now so ima get the 1st 1 well save me 30$ as well then maybe later on this year I might get the 2nd 1

what does the patch do?
add online multiplayer?

yes
also adds more content and raises the level cap

Are you 100% sure?

This is where I read that we are getting the major update Japan recently got
http://www.siliconera.com/2014/08/12/sword-art-online-hollow-fragment-get-dlc-costumes-launch/

I didnt see anything about adding online co op in that article unless i missed it

i know it was mentioned in articles somewhere and I know a lot of people have been talking about it, but I can't find the exact article that mentions it

Ill probably get it reguardless but co op would be nice
i know it has local co op maybe thats what u seen

no i remember seeing online being mentioned somewhere as well and i remember it not being built in at launch either