Wow. UA online is a little scary (like that is something new)! I just finished booking flights for myself and a traveling companion online. I logged in to my account, bought the ticket, requested the upgrade (miles), and logged out.

Then, not closing my browser or deleting history, which I guess I should have done, I logged in to my friend's account and bought his ticket and requested his upgrade with his miles. I noticed that he didn't have any e-500's listed. Which I know he has. So after that itinerary was done I went searching for where I could see his e-500 balance. When I found it, it had HIS name, with MY ACCOUNT NUMBER, and showing MY e-500 BALANCE!

So, I logged out, cleared history, closed the browser, then went back and logged in again for him and it was now showing an appropriate e-500 balance for him (quite a bit less than mine) and there was no sign of my name or MP number. I made sure the flights that were purchased were indeed under his MP number and his miles used for upgrades. But wow - how after purchasing tickets it went back to my account number for e-500's, particularly when his name became associated with my account number is just darn scary! (and I didn't print the screen showing it ... should have thought of that, but I actually panicked in a WTH kinda way)...