Reports about those new H10 versions have been circulating already since quite a while, now they are all official.
The H10 family is PlaysForSure compatible, works seamlessly with Windows Media Player 10 and features support for Auto Sync to sync music, photos and playlists between PCs and H10 players.
The 5GB H10 is currently available for $249.99. The 20GB and 6GB H10s are shipping now with a suggested retail price of USD $299.99 and $279.99 respectively. The H10 1GB will begin shipping in June 2005 with a suggested retail price of $229.99 (ouch!).
More details in iRiver press-release.