> It's also not clear why Google killed Blogger.
Because they kept chasing "the next big thing" aka "the next product to give me promotion inside the company".
Remember Google Wave? Knoll? Plus? Orkut? Spaces? iGoogle and Sites? Slide? Jaiku? Buzz? Aardvark?...
(I had to scroll through https://killedbygoogle.com to remember some of them)
More investment in Blogger with better linking between blogs (the way you can @someone on Twitter) and discovery (#tag searches allowing you to see posts from multiple blogs, curated blogrolls), more realtime/live logging functionality, easy microblogging functionality, etc. would probably have led to a lot more content existing on Google owned spaces, as opposed to being siloed behind Facebook and Twitter paywalls.