According to Gamefan Online, the release date for Sonic The Hedgehog Pocket has been officially confirmed for Japanese release! Two of the most highly-anticipated NGPC games have now been given Japanese release dates in the month of December. Sonic the Hedgehog Pocket Adventure will ship on the 16th (selling for around $36 US). This will be followed on the 22nd with the fighting version of SNK vs. Capcom (selling for $41 US).
No box art has been released yet of the game
Source: IGN Pocket