I honestly wouldn't be surprised given how they own just about everything now. I just don't know how I'd feel if it did buy DC one day I mean would that mean a merger for Marvel and DC or would they still exist as separate brands under Disney's banner? Personally I'd rather they exist as separate brands under Disney's banner but if they did merge I'd rather they do it under the pretense of some sort of Crisis style event where their two worlds and histories merge.
However I just don't see the two worlds meshing well I mean I doubt Galactus would be tolerated even if he is a necessary evil him destroying worlds would conflict with the Green Lanters a lot I imagine. Though I do think it would be interesting seeing Galactus make a herald out of a DC character. I can see Galactus creating a team of heralds after being inspired by the Green Lantern Corps but that'd cause more conflict.