EDIT:
This is a very old question, when escaped_fragment was necessary for search engines, but nowadays, search engines do understand Javascript very well, so this question becomes irrelevant.
===========
I was wondering how much SEO friendly could Polymer be.
As all the code is fully dynamic like Angular, how can the search engines pick up the information of the page? Because also doing things in Angular, I really had a hard time making it SEO friendly.
Will there be a tool to generate the escaped_fragment automatically to feed the search engines?
I guess Google may have thought of the solution, but I wasn't able to find it (even on Google).
According to the Polymer FAQ all we have is
Crawlers understand custom elements? How does SEO work?
They don’t. However, search engines have been dealing with heavy AJAX based application for some time now. Moving away from JS and being more declarative is a good thing and will generally make things better.
http://www.polymer-project.org/faq.html#seo
Not very helpful
This question has bothered me also. The polymer team has this to say about it, looks promising!
Also figure it's worth adding some context from the conversation on the polymer list, with some helpful information as to the status from Eric Bidelman.
Initial examination of the structure of the Polymer site suggests that it serving up static content with shadow-DOM content already inlined in the page. Each HTML file can be loaded from the server directly, via HTTP GET, and subsequent navigation uses pushState (documentation) to inject pages into the current DOM if pushState and JavaScript is supported.
It's recommended to use pushState over _escaped_fragment_, since it's slightly less messy, but you'll still need to do regular templating on the server. See The Moz Blog for more information on this.
I may have missed or misinterpreted some things here, and this is just a quick peek at the guts of the page, but hopefully this helps.