I'm a little late on updating this but there was an announcement that the beta will begin on Tuesday, September 27 if you got the Medal of Honor Limited Edition or you preordered your digital PC copy on Origin. For those who don't get early access, (a whopping 2 days) you will get to start playing on the 29th.
As far as system requirements, they finally released those too..
MINIMUM SYSTEM REQUIREMENTS
OS: WINDOWS VISTA (SERVICE PACK 2) 32-BIT
PROCESSOR: 2 GHZ DUAL CORE (CORE 2 DUO 2.4 GHZ OR ALTHON X2 2.7 GHZ)
MEMORY: 2 GB
HARD DRIVE: 20 GB
GRAPHICS CARD (AMD): DIRECTX 10.1 COMPATIBLE WITH 512 MB RAM (ATI RADEON 3000, 4000, 5000 OR 6000 SERIES, WITH ATI RADEON 3870 OR HIGHER PERFORMANCE)
GRAPHICS CARD (NVIDIA): DIRECTX 10.0 COMPATIBLE WITH 512 MB RAM (NVIDIA GEFORCE 8, 9, 200, 300, 400 OR 500 SERIES WITH NVIDIA GEFORCE 8800 GT OR HIGHER PERFORMANCE)
SOUND CARD: DIRECTX COMPATIBLE
KEYBOARD AND MOUSE
DVD ROM DRIVE
RECOMMENDED SYSTEM REQUIREMENTS
OS: WINDOWS 7 64-BIT
PROCESSOR: QUAD-CORE CPU
MEMORY: 4 GB
HARD DRIVE: 20 GB
GRAPHICS CARD: DIRECTX 11 COMPATIBLE WITH 1024 MB RAM (NVIDIA GEFORCE GTX 560 OR ATI RADEON 6950)
SOUND CARD: DIRECTX COMPATIBLE
KEYBOARD AND MOUSE
DVD ROM DRIVE
The beta will also end on October 10th.