"Have more big news coming Tues morning...make sure you're watching @GMA! You definitely aren't going to want to miss this," she wrote.
Obviously, we couldn't wait to hear what BritBrit had to say--or could we have?
Unfortunately, Britney's surprise was spoiled by TMZ as they published all the details of what she had planned.
Apparently, the "big news" is about her Las Vegas show and she will be revealing all the details from an undisclosed location somewhere in the desert, where Britney will be arriving via helicopter to a crowd of 1,350 people.
She will perform her new single "Work B*tch" and then will drop more deets about her upcoming Vegas show, but will probably leave out the fun fact that she'll be making $310,000 per show.
All of this will be broadcast live on Good Morning America tomorrow morning, but now that we know all about it, it's a little less exciting.
This definitely hasn't been Britney's week--first, her new single leaked online a day ahead of the scheduled release date and now her big surprise was spoiled.
Will you watch Britney's GMA appearance, anyway?