Just noted that Tim asked the question whether GoogleAppEngine was a lock-in strategy?
I've made a comment on the radar, but I thought I'd leave a copy here for reference.
I feel like I'm pointing out the obvious and just repeating what I talked about at OSCON. Then I realise you already know all of this and are just getting the conversation going.
In my view, the real innovation in GoogleAppEngine (GAE) is the open SDK and the possibility that open SDK compliant environments can be re-implemented elsewhere (including on Amazon’s web services). The difference between Google and Amazon is that Google has taken the approach of creating an open sourced standard and in effect encouraging competition. Amazon has always been about their “secret sauce”.
Whilst GAE is at the level of a framework and Amazon is at the level of infrastructure, the approach of an open sourced standard, if adopted, is likely to spread up and down the stack whether this is at SaaS, PaaS, HaaS or whatever other aaS people choose.