Originally Posted by Mootsfox
CF development has pretty much stopped. What made CF appealing long ago is that it is based heavily on IDE/ATA. SD cards can currently beat out all but the fastest (and wildly expensive) CF cards. There was a standard proposed by Sony and NIkon for CFast, which would use the SATA protocols, but that has not seen the light of day yet.
Most new pro cameras have dual slots, with either Dual CF, Dual SD or one of each. SD is a stronger, faster, more widely supported and cheaper (to build and buy) interface. CF is outdated.
CFast has actually shown it's face in the embedded PC industry. Traditionally industrial-grade CF cards have been (and are still) used as a sort of SSD for embedded devices and sometimes even thin clients. Check out the VIA Artigo 1200 for example.
Also, for PC use, CF cards are still a by far better choice than SD due to two reasons: first, the IDE compatibility that you mentioned, and second, they are generally faster when it comes to random reads/writes. Also, due to the larger size they can still make models that use SLC flash at reasonable capacities.