Hell Has Frozen Over: Britney Spears And Christina Aguilera Announce Co-Headlining Tour

Earlier this week, things were looking pretty shaky for Britney Spears' upcoming summer tour once Enrique Iglesias bailed on the supposed co-headlining trek hours after Brit announced the gigs on Good Morning America. And since then, everyone from Usher to Nicki Minaj has been mentioned as possible replacements on the joint venture. (Though I'm still perplexed as to why Britney needs to share a bill with anyone. Didn't this broad break the bank with her last tour?)

Thankfully for Spears diehards, the Femme Fatale ended the suspense (and pretty pretty much caused a collective "Huh?!") when she tweeted that her onetime rival in all things pop, Christina Aguilera, will be joining her on the road from June through August:

"I'm so happy to reveal my secret to all of you all that my OLD friend @theRealXtina and I are going on tour together this summer. 2 bionic women, 2 femme fatales! xo - Brit"

I actually had to read that four times to believe it.

Until the concerts kick off in mid-June, Xtina will be slumming fulfilling her judging duties alongside Cee Lo Green, Adam Levine and Blake Shelton on upcoming NBC reality music competition The Voice, which debuts in April.

Meanwhile, can you imagine the fiery, dueling tour riders these two broads will have? Like, what happens when Britney's dumptruck full of Cheetos and Xtina's classy catering truck show up backstage at the same time, and cause a traffic jam while crew is trying to unload lighting rigs?

But forget that for a minute—what songs will Aguilera be performing? Will she be doing tracks off Bionic, which, at this point, was released nearly a year ago? Will it be a greatest hits-type show?  WHAT IS GOING ON?

I guess the most important thing to remember is...Happy April Fool's Day.