I was setting up this site with a temp url: http://domainname.tempdomain.com. 
Once everything was set and the domain was ready to be switched to the new site the portal aliases were updated. 
The temp alias was removed and everything seemed to work great. 

The blog was updated fine except the Permalinks still showed the temp url. 
I selected 'regenerate permalinks', unselected trackback links options and it continues to show. 

This is a real issue as this is the link that twitterfeed passes to twitter and the link twitter displays to the blog entry. 
Where o' where is this stored as I can't find it in any of the blog or aspnet tables, site_settings, or host_settings tables. 

Actual tag entry: (gt and lt replaced with ^ symbols for forum) 
^guid isPermaLink="true"^ 
http://domainname.temp_domain_name...... 
^/guid^