YES within (3) days with most firms. I called Etrade about that because awhile ago alot were worried about not being able to trade during the run. Etrade said you can call them as soon as symbol changed and they will correct with new sym. or tradefor you with a call.
Cussip change: I was in FCNK a while back before it changed to RGNO. Upon changing we had a monster run. I had Scottrade and ChoiceTrade at the time. My ST shares were frozen and my CT shares were available (for internet trades). You will probably be able to call a trade in right away, but with ST, it took a while before they allowed internet trades. This may be a problem for some people at work who don't want to use the phone in front of their boss... Just giving you a heads up :) i think this could run big with the new symbol; shorts covering and new interest :) RGNO sure was a blast!! GLTA