I would like to see a 1.4d addition: Dual-link HDMI using two ports.
Some PC Games look very cool with 1080p24 3D but they are practically unplayable with 24fps (at least it hurts my eyes, even with RPG, not to mention FPS games...), 720p60 3D is smooth (very noticeable if you just switched from 1080p24) but looks worse than 1080p60 2D.
1080p60(50) 3D could be very nice. May be I would consider it to use glasses for games which look nice in 3D.
If we consider that nobody wants a new cable which is not backward compatible than may be we should use two cables at once to achieve 1080p60 3D (or at least 1080p50 3D if they resist to keep the max TDMS clock below ~250Mhz)
And I suspect it could be possible with some existing 1.4 hardwares through a firmware update (which will never happen).
"DIY certified hobby-calibrator" (based on ChadB's "warning signs" list