Just posted on the iRiver website,

iRiver China announcement

Website (chinese)
http://www.iriverchina.com/company/news_vi...iew.asp?idx=347

Translated (Babelfish)

The next edition icHp-100 firmware officially will provide to 500kbps below the OGG music document support, soon will issue
The icFp-300 firmware also has to the OGG support progresses,160kbps and the 192kbps test passes, after will continue to promote its performance to issue.
But icFp-100 supports OGG the possible not big.iRiver technology engineer already with every effort completed for the user, hopes could continue to obtain the user
Understanding and support

Looks like support for the iHP-100 soon and the iFP-3xx series along the line somewhere, not looking good for the iFP-1xx's. No mention of the iMP's either.

(Thanks to jEaLoUsY nEvEr DiEs for posting this on the iRiver forum)