As far as I know, Google will index a page if it meets at least one of two conditions:
http://www.example.com/#!/page-name
If I have that right, then meteor apps (like meteor.com, which lacks content when javascript is off) won't be indexed by Google.
Did I miss something? Is there some other mechanism in play or planned to make meteor apps indexable?
tl;dr: Simple indexing is now included in the spiderable package, more features are planned for an upcoming release.
Recently added to the meteor FAQ:
Can Meteor serve static HTML? Can Meteor sites be indexed by Google?
Yes. Add the "spiderable" smart package to include support for emitting static HTML to search engines, complete with valid links. The spiderable package implements Google's AJAX Crawling Specification. See the spiderable documentation for details.
This version of spiderable is specifically for search engines. A future version of Meteor will also send HTML to web browsers on initial page load. The Meteor templating system was designed specifically to support this use case.