Intel Z87 To Have All 6Gbps SATA, Dispense With Legacy I/O
According to a report by Fudzilla, Intel's upcoming Z87 platform for 22nm Haswell CPUs will be the first to bite the bullet and dispense with some older standards which have been around for some time. Replacing the Z77, Z87 will form the basis of the mainstream high-end for Intel systems upon the release of their new CPU expected late 2013/early 2014.
The most notable loss will be support for PCI, the venerable interface standard created in 1993 and a staple of motherboard design for most of the last two decades. At a stroke your legacy components such as sound and network cards will be incompatible, but generally speaking PCI devices haven't been part of the mainstream for years apart from these two examples. If you're looking at picking up a sound card in the next year or so that's probably worth keeping in mind.
Additionally, SATAII limitations on the majority of the on-board ports will be nixed, with all six running at SATAIII 6Gbps. As SSDs and hybrid drives become more affordable and prevalent this should alleviate some of the port-shuffle which often goes on to try and retain optimum speed on all your storage during an upgrade. There appears to be no indication that a 'faster than SATAIII' interface is due on Z87.
Other features such as USB 2.0 and PCI-Express 2.0/2.1 will probably remain on the platform for some time, chiefly due to cost and lack of demand for the faster protocol across all devices. PCI-E 3.0 will of course be via Haswell's onboard controller.