How did you possibly create this thread and not see the sticky post at the very top ? http://forums.digitalpoint.com/showthread.php?t=1518279 There is a whole year of "Which is best Blogger or Wordpresss" reasons for you to go through.
Blogspot or wordpress? Both are very important in their places. But as far as i see, priority is given to blogspot because Google created it. Also, when you make any blog on blogspot and wordpress then Google firstly index your that blog which you made on blogspot. The one more benefit of Blogspot is that if you make a free blog then you can easily put Google analytics code in it to start tracking the incoming traffic to your blog but in wordpress, now analytics can't be installed. It can only installed in paid wordpress domain, not in free wordpress blog like blogspot.
There is absolutely no truth to any of this. Why do people keep circulating this non-sense? Google doesn't not give "priority" to anything, especially not the spam filled splog network that they are trying to clean up, called Blogger. The only thing true about this is that Google owns Blogger. There is no significant difference in anything else. You are not going to get any more of an SEO boost on Blogger than you would on any other platform.
Both are good to my opinion, but: 1. Wordpress.com -You can't edit the layout (html/css) unless you pay extra upgrade for css -You can't add advertisements 2. Blogger. -You can edit html or css -You can add ads