I don't think that Boutiques.com was a departure from what Google is already good at. Boutiques.com contributes to their core product (search).

On the surface, it looks like Google has defined a long list of fashion ecommerce sites to search. Then, they pepper in some Google Images functionality along with a base template designed to encourage engagement.

This sounds a lot a specialized, properly linked version of Google Images more than innovation.

I think that Google should be investing more in startups if they want to increase innovation. Creating products that contribute to their core product is exactly what I'd do if I was the CEO of Google.... which based on my bank balance, I'm not :)