Any idea on which graphic card will they use for the new top-end iMac? Nvidia just unveiled the new GTX 880m, which is basically a rebranded 780m, and still Kepler. It would be great if Nvidia was holding a 880MX for the new iMac, just like they did with the 2012 model and the 680MX.
Another option is going with AMD...
One of the reasons I'm holding off - DDR4 + better flash + better GPU. I'm sitting on a 680MX iMac right now and it'll be all good for at least another year or two (I'll probably donate it or sell it to a relative) with Skylake being something worth while holding back for which will be around 2015 - especially looking forward to seeing it in a MacBook Air with the improved GPU.