What does it means to you?
-If you don't use my plugin, not too much. Maybe you can take a look at it anyway if you are a FCKeditor user and don't like embeds.
-If you use the plugin, but are using a version of SWFObject hosted in your server, then you don't need to upgrade my plugin. Anyway, you might want to upgrade your copy of SWFObject, and if you place it with a different filename, then the upgrade of my plugin might be useful or you might end up including in the pages a link to the old library and another to the new one. Sorry, I didn't thought about it.
-If you are using the plugin and are relying on the externally hosted library, then it would be good to upgrade the plugin. The caveat is that you need to open and save again any page with a reference to the plugin to get it updated (unless your CMS has some option to do a search&replace in all the content). The good part is that even if you don't touch the existing content, the new files will use the new version.