This is an area of vital importance to public, JS-based RIAs, and needs some real innovation. Why even bother delivering this half-baked solution? The processing cost makes it untenable for all but the tiniest of URL-spaces.
The "real solution" is coming, and we will get it right. It's connected to URL routing, and sending down initial HTML on page load. We're all excited for the day when Meteor apps initialize the client session on the server. It will look at first glance like a traditional server-side app. :)
I have tried zombie but there were various issues with getting it to work. Phantomjs was just much more painless.
Because we used it for our funding announcement at the end of last month -- a full press cycle, where the Andreessen Horowitz and Matrix Partners press machine pushed our story out to all of the tech blogs, with all of the traffic that that implies -- and not only did it work fine, it got us to #1 on Google for "meteor." Above, you know, actual meteors :)
It works fine for us as a stopgap measure and we wanted to share it with others. We put it in a optional smart package that isn't included in new projects by default.
We're near the end of a major rewrite of Meteor's page update engine. You can see the latest progress on the 'spark' branch. One thing that happened during this rewrite was the conversion of Meteor's templating to be 100% string-based. Check it out: go to meteor.com/faq, open your browser console, and evaluate "Template.faq()".
This means that the server can render the templates for your app without having a DOM implementation of any kind (much less a headless client.) 'spiderable' doesn't do this yet, but it will by Meteor 1.0 (if 1.0 even has a separate package.)
For the record, the ratio of our investment in auth and accounts, to our investment in Spark, is about 2:1.
Elegant proof if any were needed that so-called SEO is merely tricks for polluting search indexes. As bad as spammers.
If you really want the Wikipedia page for meteors, nothing's stopping you from going straight there.
I think people's confusion lies in the fact that there are actually two separate areas where javascript is run in Phantom: one is the javascript that controls Phantom and has a filesystem API; the other is the javascript that gets run inside the browser sandbox as part of the web page, just like any other javascript run in any other browser. It is possible to set up a bridge between the two such that the latter can issue commands to the former, just as you can curl sites and pipe them into bash. The point is that with default settings you can use PhantomJS to load a website without any danger whatsoever.
If you disagree, please write a more worthwhile comment showing me which part of the API is dangerous.