Yep, the pair are set to walk down the aisle this afternoon after none other than Olly Murs let the cat out of his designer weekend bag in an interview with Capital FM.
"I'm there on Friday," he goofed. "Very, very excited about it. I think the whole country knows when their wedding is, so I'm looking forward to it.
"I'm looking forward to seeing some people I haven't seen in a while. It's going to be a really interesting day. I hope I don't get too many drinks down me because I've got a gig the next day so I need to be on my best behaviour."
And whilst there's been a lot of secrecy around the big day itself, we've managed to uncover a few of the finer details ahead of us all cooing over their star-studded wedding photos.
1. Marv and Roch will be tying the knot at 18th century mansion, Blenheim Palace in Oxfordshire and are said to have spent thousands on the venue alone. A insider revealed: "Rochelle fell in love with Blenheim when she went to see it and loves the history of the place. The gardens are beautiful and she can't wait to have her wedding pictures done surrounded by her nearest and dearest."
2. Rochelle's wedding gown is thought to be from Browns Brides boutique in London, which specialises in designer dresses from the likes of Vera Wang, Caroline Herrara, Valentino and Alberta Ferretti. Classy.
Final fitting? Rochelle was spotted at the Browns Brides boutique earlier this week
4. The rest of JLS - Aston, Oritse and JB - are rumoured to be ushers. No word on who's been chosen to be best man though. Tricky.
5. Myleene Klass has decided not to attend to avoid seeing her ex, Graham Quinn, who is an usher. A source told the Evening Standard: "Myleene gave up her invitation to the wedding to avoid any kind of stand-off between her and Graham. Things are still raw between them and there's no way she'd want it to affect Marvin and Rochelle's big day."
6. Alexandra Burke will perform at the wedding bash. She told Key 103 Live: "It's a surprise, she doesn't know." Ahem. We think she might now, Alex.
7. Craig David (remember him? He looks a bit different these days) has also been asked by the bride and groom to perform. Ooooh, is that Craig and Alex singing Endless Love we can hear? Fingers crossed!
Congrats to them both!