Hi, I installed the Facebook Like button Javascript version on my website on December 15th. Take a look at this report from Google Webmaster Central.

Crawl stats Googlebot activity in the last 90 days

The crawl stats are from Googlebot which as far as I know doesn't execute Javascript. Could the Facebook Like Javascript code, "The XFBML version" be related to large spike in Time spent downloading a page? (By the way the huge spike in November was caused by a mistake where every image request was getting a 301.)
I'm not sure what caused the spike to go down by half somewhere in December. It may have been related to a faulty setting in web.config. I'm at a loss as to what I can do about this or even how to tell if this is my problem or Googlebots crawl problem.

Here is the Facebook code I am using to create the like button. It is right after the opening body tag <div id="fb-root"></div>
<script> window.fbAsyncInit = function() { FB.init({appId: 'xxxxx', status: true, cookie: true, xfbml: true}); };
(function() { var e = document.createElement('script'); e.async = true; e.src = document.location.protocol + '//connect.facebook.net/en_US/all.js'; document.getElementById('fb-root').appendChild(e); }()); `

and this creates the like box:
<fb:like show_faces="false"></fb:like>

If the Javascript can't be the problem any ideas on where to start looking would be appreciated.