Disclosure: I'm long V & MA presently in my core acct... However, I do expect a 'sell-on-the-news' reaction will kick in tomorrow morning after MA reports only because I believe their earnings have already been priced in.
Therefore, if they simply meet...MA will sell-off considerably. If they slightly beat, the sell-of will be less severe.
In other words, she'll probably sell off 1-2% at most.
For MA to really move higher tomorrow, they really need to blowout the #s as well as raise their outlook for next Q... Something no one is expecting right now.
MA is cheaper than V at this point going forward and has significantly underperformed V year to date, which is rare looking back. I expect MA will touch $480 sooner rather than later, that level would match Visa's year to date performance. All depends on earnings though, as you stated. long MA as well, good luck