Mike Arrington's a bit peeved at Google. His post is a good vent, but to me the key bit was way down in comment number 33:
"...my main gripe is that I want to understand what Google’s overall game plan is. I just don’t see it."
Nobody knows what Google's grand plan is - I suspect not even Google. Here's what I wrote in my post on Google Spreadsheet (nb: written the day before its release):
"So in the final analysis, the main benefit of web-based Office products is that they'll extend the functionality of desktop office products in many useful ways. I expect Google Spreadsheet to do all these things, but almost certainly in a beta form to begin with. If this release is like all the other Google betas, the functionality will be a bit clumsy to begin with - but watch closely as they iterate it over time into a very powerful web-based product (like they did with Gmail, etc)."
And that right there is Google's "overall game plan" - to release clumsy web apps and iterate them until they extend the functionality that we're used to. It won't always work - Froogle anyone? But they've changed the game before - I'd argue three times. First with search, then with online advertising, and thirdly with email (obviously not to the same degree as the other two!).
That's what makes Google so dangerous. You never know what you're gonna get.