You`ll definitely want insurance. Apple, for example, is well know for going after bloggers who publish information before they announce it officially. You may also like to consider using a company structure to add a bit of extra distance.
PS: It`s great to see another startup keeping a blog of how things are going. I decided to try it for my next project after reading Diary of Startup.
I agree.
The risk may be somewhat remote... I`m not sure what you`re blogging about. But it sounds like a smart move.