My Review:

Both players support 1080p HD videos, both can play video over LAN, both can play video from USB flash disks, USB hard drives, both can play images of DVD-Video and Blu-Ray discs.

ASUS HDP-R3 O!Play and WD TV Live support wireless connection (with a separately purchased Wi-Fi adapter), but ASUS HDP-R1 O!Play doesn't support this.

Advantages of ASUS O!Play R1:
- FLV support
- better remote control

Advantages of WD TV Live:
- Pandora streaming music (and hopefully more streaming media services in the future)
- Dolby Digital and DTS support
- DLNA


Disadvantages of ASUS O!Play:
- Problems with Qpel & GMC Warp point 3
- Doesn't support ID3 tags for music files except for MP3 songs
- DTS HD and DD TrueHD not supported
- Problems with MKV container
- Wi-Fi not supported
- Streaming internet services not supported

Disadvantages of WD TV Live:
- Some users have network connection problems
- Cooling
- Remote control could be better