Can I now make withdrawals/deposits to my JP Morgan Chase account at WaMu locations?

Andrew, I’m sorry. I don’t know.
Why not ask Chase ?

Negative. Wamu is still Wamu (for now). For example, HP owns Compaq, and if something’s wrong with Compaq then HP will take care of it, but a Compaq laptop sale is only for compaq lappies.

Not yet. The transition will occur over the next year or so.

(disclosure: my wife is a senior loan officer for Chase.)

You can make withdrawals but not deposits at WaMu ATMs.

http://austin.bizjournals.com/austin/stories/2008/10/06/daily44.html?ana=yfcpc

They say the transition will take about a year, but I have friends whose banks were taken over by Bank of America years ago, and they still have issues all the time. I would stick to using the Chase branches for your Chase transactions for the foreseeable future.