There are a whole host of thoughts provoked by this post, but the most prevalent is that an acquisition of Canonical would do precisely zip to further Google's strategy of moving everything into the cloud.
The author seems to think that Microsoft is some sort of threat to Google. The last time I checked, Microsoft was only a threat to Microsoft. Both Apple AND Google have made it abundantly clear that their futures lie in the cloud. Google has no use for "fat" client software - their vision establishes the cloud as a file system and the web as a shell.
While I agree that Ubuntu could certainly benefit from a large cash infusion from a benefactor like Google, it provides very little value for Google's long-term strategy.