inventfilm

When importing your blog from blogger you may cause your posts to reappear as duplicates in your subscribers feed readers, unless you install this plugin and set the “Not Before” date to the day you switch.
This plugin works best if you have already been using feedburner to “burn” your feeds in blogger.
<h4>Why would I use this plugin?</h4>
If you are using blogger and feedburner, then after you import your posts into wordpress and change your feedburner “Original Feed”, your subscribers will see all your old posts reappear in their news readers as new unread posts. This plugin allows you to remove all those “old posts” from the rss feed which, after switched the feedburner feed source, will make the blogger to wordpress transition completely seamless.

RSS Not Before

RSS Not Before provides the ability to remove posts from the rss feeds prior to a given date.

Poco

If you have ever imported a Blogger blog into WordPress you probably have some posts that were originally missing a title. During the import, a title (and post slug) was created for the post that looks like a large numerical value. I believe this is the original Blogger post ID, I guess the importer needed something to use.
What this plugin does is replace those ugly numerical titles with the first few words of your post, like Blogger did. By simply enabling the plugin, any post that matches the ?ugly title? filter will have the title replaced by the first 48 characters of the post.

Blogger Title Fix

This plugin replaces the random title given to posts that were imported from Blogger with an excerpt.

RSS Not Before vs Blogger Title Fix