From what I can tell TicketMaster.com will direct you to the ticketsnow site if you click on one of the shows on-sale today...this might change come 10:00am.
Livenation will allow you to buy the tickets at 10, but most likely will direct you to a Ticketmaster site. If your CC info is stored on Ticketmaster you should be fine. Livenation.com itself will not store your CC info, it has to be on TM