Western Digital's recent forays into boxes that plug into TVs have tended towards the network-centric, with both the tinyand WD TV Live Hub both working on the premise of streaming at least some of your content to the TV from other sources.
The Elements play doesn't think like that, and is, in essence, the original WD TV with a one or two-terabyte hard drive in it. The remote's the same, the menus are similar, and the only thing that marks the Elements Play out is that it's much larger than the Live or original WD TV. In other words, if you want a big black box to throw under your TV, the WD Elements Play is it. There's only so much excitment you can get about a big black featureless box, after all.
The Elements Play is an odd kind of transitional AV box. It's not a streamer, the way the WD TV Live or Live Hub are, but it's also not just a conversion and playback box in the style of the original WD TV. This means that the connections on offer are a little different. On the AV side, it supports HDMI and component out, as well as optical audio and USB out for connecting the system up to a PC for file transfers. A single USB A type socket on the side allows for connection of standard USB mass storage devices.
From Western Digital's website, it's suggested that the Elements Play supports "popular" media formats. Digging a little deeper into the product manual, it's stated that on the video side, AVI (XviD, AVC, MPEG-1/2/4), MPG/MPEG, VOB/ISO, MP4/MOV (MPEG-4, H.264), MKV (H.264, x.264, AVC, MPEG-1/2/4), TS/TP/M2TS (MPEG-1/2/4, AVC), FLV (D1 resolution only) and RM or RMVB 8/9/10 are the specific formats it'll play back. On the audio side, MP3, WAV/PCM/LPCM, WMA, AAC, FLAC, MKA, OGG, APE and Dolby Digital (inside video files only) are supported.