the only thing i would add to the discussion that hasnt already been covered (and argued about
)
..is that if you use
domain . com/blog/ arrangement (edit lol @ there always being a site of this name when youre trying to use examples, clever domain choice by domain . com )
.. and you have the site and blog interlinked correctly you can make the blog posts appear as sub pages of the main site pages in the SERP, hence allowing brand new content to rank with the authority of older established site pages.
this doesnt appear to be possible, (or at least easy anyway) with blog. domain. com setup from our testing.