New EF 70-300 f/4-5.6 IS?
I've received an email saying Canon will be replacing the 70-300 f/4-5.6 IS with a new version.
The current version was launched in 2005 and has been a good seller for Canon.
I have heard stories from various retailers about the lens being backordered for a while now.
I'm going to say the likelihood of this being replaced is low, unless I hear from better sources.
These are still easy to get from Canon, I do not see a replacement.