Perhaps you didn't mean it that way, but that's not a photo of a real car. It's an altered rendering using of one of the original 12C coupe press images. McLaren have not yet released anything official - photographs or press info - confirming the convertible version of the 12C.
However...
One solid clue towards McLaren's future plans was revealed (perhaps accidentally?) in one of the early floorplan images they released of the new McLaren Production Centre.
In it you can clearly see a section labeled "Webasto RHT Sub Assy"
Webasto is a German company that makes, among other things, convertible tops for different manufacturers.
The "RHT" in McLaren's description seems to imply that the 12C Spider (or whatever they eventually call it) will have a 'Retractable Hard Top'. I look forward to seeing how it is all packaged together as well as the weight difference from the Coupe. It may not change much since the chassis should not require extra strengthening like most cut-coupe convertibles.
>8^)
ER