It makes sense, in a way. SF4 is on the "Taito Type X2" arcade system, which is pretty much a PC in a cabinet. Behold!
Taito Type X2
* OS: Microsoft Windows XP Embedded SP2 [2]
* CPU: Intel Core 2 Duo E6400/Pentium 4 651/Celeron D 352 (up to latest Core 2 CPUs supported by the chipset)
* Chipset: Intel Q965 + ICH8
* Monitor: 720p/1080p/1440p HD LCD Monitor
* RAM: DDR2 667/800MHz (512MB/1GB, up to 4GB)
* GPU: PCI Express x16-based graphics. Support cards include ATI RADEON X1600Pro/X1300LE or nVIDIA GeForce 7900GS/7600GS/7300GS, up to latest graphic cards (Radeon HD 3800 or Geforce 9800 series)
* Sound: Onboard Realtek HD 7.1 channel Sound (supports add-in sound cards)
* LAN: 10/100/1000 BASE-T
* I/O ports: 1x JVS, 4x USB 2.0 (up to

, 1x serial (max 2), 1x parallel port, 2x PS/2, 2x SATA
* Audio inputs: AKG C535EB Stage Microphone, line-in (Surround 7.1)
* Audio outputs: 7.1, SPDI/FX
* Expansion Slots: 1x PCI Express x16 (used by video card), 1x PCI Express x4, 2x PCI
* Storage: 2x 80 GB 10k RPM SATA Hard Drives
* Media: 80 GB 10000 rpm Hard Drive
So it won't take much effort at all to release on PC proper.