From the announcement:
A new 4th edition, funded on Kickstarter, will be available in June 2013. The game is in final production now (locally) and will be shipped before the end of the month. The final artwork and graphics are fantastic.
The success of the Kickstarter campaign has made Napoléon better for everyone - all 4th edition copies will have metallic foil unit labels and a deluxe map and battleboards.