Well.... hmmm... I thought I had an answer but now I think there are a couple options. Someone else ck me out here and tell me if this is right.
If you stay on blogger hosting and get a new domain that redirects for branding purposes and to shorten the URL the SE spiders will pick up the link to shortname.com and follow it to longnameatblogspot. So they will index the content at blogspot and your domain won't get any PR or SE rankings. However it would still be better for marketing and branding.
But if you hosted the new domain you could FTP your blogspot blog to the new domain so you would have a REAL blog you own on your own domain. The downside there is unless you worked on a link campaign is you would have no inbound links and the new site would probably be sandboxed and would not be on the popular blogspot domain so your traffic would probably really drop. Plus you would have to pay for hosting. But ultimately long term if this is an important blog it's really best to have it on your own domain.
What do you guys say???
(Edited to add Bobbie we answered at the same time
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