I know I want one of them, but Im not sure which.
Amazon integration seems better, already integration with Plex and more third party dev work underway. It also had the options of using the Dot in other rooms, making it cheaper for multi-room setups. Also integrates well with Fire Stick and box.
Google appears to have access to more information but much less third party compatibility, also very expensive to have more than one in a setup.
I think Im going to have to wait to see how the respective development improves for each platform.
In terms of integration as long as the other services have an API opening up to Google Home is easy, they have already listed partners such as smartthings which I already use for full home automation.
I see your point in terms of cost, but wouldn't surprise me if Google release a dot equivalent in the future, possibly part of the chromecasts. Remember that mobile integration is already there which android doesn't have and Home will work with any chromecast device..
I expect the technology and integrations will be much of a muchness once Home catches up, but Google I think have the better AI and ability to hold a conversation.
Had Home not been released I would have went straight for the echo! But the openness of Home I think will give it the better experience, they aren't limiting to android tech either although that would open up to head units and TVs... I do wonder if you could just pick up a cheap android box to work as a dot like device?