I became aware of this situation through Penny Arcade. I think Tycho makes a sad, yet true, viewpoint. I support developers having views and opinions of their own games. However when people see user reviews, they expect that they come from an unbiased consumer. It's really unfair as even politicians can vote for themselves. I can see how people can see it as a deceiving tactic if you don't announce that you worked on the game. I agree that the developer blog would be ideal for this. I enjoy reading what developers thought of a game they made (although it is usually comparing it to an upcoming sequel).
While it is also sad (for humanity) that the good grammar made the posts suspicious, I think it was also the fact that they all gave the game a 10, (which is rarely given out by the more critical, unbiased reviewers) on a game that has had mixed reviews so far.