This is just at the rumour and wishlist stage currently, but Twitch were first with the stories about Spike Lee and Josh Brolin, so we can be reasonably confident when they tell us that Rooney Mara is in serious contention for the female lead in **Oldboy.
That role would be sushi chef Mi-do, played in Park Chan-wook's film by Kang Hye-jeong. Lee's new version names her as Marie, according to Twitch, so there's probably reason to suspect that she won't be preparing sushi anymore either. But she'll presumably remain the love interest, who our hero Oh Dae-su / currently-unnamed-Brolin takes a shine to along the way to solving the mystery of his fifteen-year imprisonment. There's also the threat of her death hanging over his progress, just to spice things up. Oh, and without wishing to be spoilerific, perhaps there's more to her character than is immediately revealed...
Mara, of course, is so hot right now in Hollywood, currently raging through David Fincher's The Girl With the Dragon Tattoo as Stieg Larsson's violent goth punk hacker savant Lisbeth Salander. Oldboy would make for another edgy role in another dark remake, although as we've said before, Mark Protosevich has eight volumes of manga to draw from in his screenplay, and they don't much resemble the Chan-wook classic. There's potential for this to be a very different film, but comments from you guys on our previous reports suggest you're not very convinced by that argument...
There doesn't seem to quite be a start-date for the Spike Lee Oldboy so far, but for all your current Rooney / Lisbeth needs, make sure you pick up the latest issue of Empire.