One of the most promising features of the cloud is the ability to leverage other companies' APIs to power your business. More than just saving money, it lets you do things that would be impossible for a startup to build in-house, like a search index for the whole web.
Of course there's always a downside. As Todd Vernon points out in his latest blog post, you're trusting a third-party with your company's future. This is an especial problem with Google since they tend to automate everything, so it can be near impossible to reach a real human being to fix any problems if they do decide to cut off your access. Jud Valeski spotted a classic example of this when some API providers 86-ed IP addresses on App Engine and EC2.
With those fears in mind, it was great to read Jay Parkhill's analysis of the BOSS, Bing and Google Search APIs. There's still plenty of ambiguity left in the agreements, and I've no doubt that the providers could arbitrarily cut me off despite anything in the terms, but it's a great insight into what the providers care about. It should make it a lot easier to skirt any uses that would hit hot-button issues for them, so I'm very grateful to Jay for taking the time to research this.