Hm, did you just ask, whether apples or oranges fall faster ? I could offer my PR / crawlrate analysis as a starting point, if that helps. (also see this thread: http://forums.digitalpoint.com/showthread.php?t=1467871)
I agree with Bohra. Blogs get crawl faster specially if your blog has auto pinger plugins like in wordpress.
Every time the crawler visit and the site is newly updated. By the way check this out: How to I have found this while browsing the net
I realize that when my sites update more frequent, and the backlinks in the google webmaster tools update more frequent too.
Google visits the sites which are getting regularly updated including the blogs as well as the forums on a daily basis.
Search engine prefer those websites which have frequent changes at content and get new content each and every day. If your website is getting content every day or get two or more post each day you can increase your website crawling rate or can install search engine ping services. wordpress blog have this ping services by default.
If you want to check for few sites then type url to google search box and click on "cached" link (right down of website of google result). After clicking on cached link, you can see the date and time when google has indexed that site last time.
I think only one to crawl faster is write everyday new content and ping it. Bring back links as much as you can. I hope this the way to crawl faster...