(Disclosure: I work for ICIS: About ICIS)
Shell gets an second seat on the Codexis board an makes a financial contribution. It reinforces Shell's commitment to renewables, and might make large scale commercial cellulosic ethanol a reality sooner. In 2008 the firms said they could see 2nd generation biofuels in five years.
The recent agreement is the third announcement that the two firms have made, which I've tracked. The first was recorded here on 16 November 2008 with Codexis and Shell in biofuel move.