I am looking to 301 my old blog.davelevy.info site. This would seem to be complicated by the need to transform the permalinks from ./YYYY/MM/DD/slug into ./slug. Here are my notes, 
I am using the redirection plugin and I have set up a rule to redirect from the root i.e. blogs.davelevy.info to davelevy.info/blog.
I have logged a support message on their support forum. They replied and pointed me at this page, on their site called redirect regular expressions.
I have inserted the following redirection on the target blog. ^/\d{4}/\d{2}/\d{2}/(.*) /$1/ which translates the old permalink format into the new and shorter one.
I have inserted the following rules on the old blog i.e. http://blog.davelevy,info.
^/(?!wp-admin)(.*) http://davelevy.info/$1
i.e. for everything except wp-admin, pass the URL onto the new site, I also have a rule to pass the top level blog page onto the new blog home page since the blog is no longer the home page for the new site.
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