Features include a color TFT LCD, JPG viewing, USB Hosting, OGG playback (as with all new iRiver products), MP3 recording, TXT viewing, etc...
iRiver Japan Corporation will release the "H300," a HD audio player with a 2" color LCD, in the middle of June. Both the 20GB "H320" and 40GB "H340" models will be made available, each listed as Open Price. on iRiver's direct sale site, "iriver e store," the price of the H320 is 47,800 yen, and the H340 is 59,800 yen. Supported operating systems are Windows 98 SE, ME, 2000, XP, and Mac OS X v10.2.
The player uses a 2" color TFT LCD with a 260,000 pixel resolution. In addition to an increased ease of operation with a new GUI, it features a text and photo viewer function. Lyrics can be displayed using the text viewer, and the image viewer supports the display of JPEG and BMP files.
Another function of the device is its ability to act as a USB host; this means that when the player is connected to other devices (supporting the USB Storage Class), the player can interface with other devices without the need of a PC. This includes the transfer, copying, and deleting of images stored on a digital camera, and all operations can be carried out using the player's display.
Devices with confirmed compatibility of the player's USB Host function are listed on iRiver's page, here [1]. Furthermore, although the H300 series supports USB 2.0, USB 1.1 will be used when the USB Host function is utilized.
Supported audio formats are MP3, WMA, WAV, and OGG Vorbis. Supported bitrates for MP3 are 8 ~ 320kbps, and for OGG, 32 ~ 500kbps. only fixed bitrate is supported for WMA. The playback frequency response is from 20Hz to 20kHz, and it has a S/N ratio of 90dB with MP3. The headphone output is 20mW x 2ch (16 ohms)/12mW x 2ch (32 ohms).
The player supports the USB Storage Class, and files can be easily transferred by simply dragging and dropping them through Explorer. Up to 2,000 folders, and 9,999 files are supported, and audio data management via ID3 tags and other information is supported.
It features an internal FM tuner, and can also record to MP3. A voice recorder function is also furnished, and the internal mic or an external mic can be used. The recording format is MP3, and when using an external mic, the bitrates can be from 40 ~ 320kbps, and the internal mic, 40 ~ 128kbps.
The playback function features 5 preset equalizer types such as normal, rock, and jazz, as well as a user EQ and SRS WOW effects. Using the internal lithium polymer rechargable battery, the maximum battery life is about 16 hours. An external battery pack housing 4 AA batteries is also included, which extends the battery life to about 50 hours of playback.
The headphones are Sanheiser "MX400." Although a remote controller is included, the remote does not have a LCD display. An external microphone, USB Host cable, and AC adapter are included. Also, a the H340 includes a USB cradle with a recharding function.
The external dimensions and weight of the H320 is 62 x 22 x 103mm (W x D x H) at 183g, and the H340 is 62 x 25 x 103mm (W x D x H) at 203g.

Inspired by:
http://www.watch.impress.co.jp/av/docs/20040528/iriver.htm [2]
Product Information:
http://www.iriver.co.jp/product/index.php?p_name=H300 [3]