bill - 2:13 am on Jul 4, 2007 (gmt 0) It is interesting that they're advising people to use the archive.org version instead.
I'd mis-read the title of your initial post. I kept thinking the deadline was July 7th. ;) Doh!
If you are a software developer, use this time to ensure that your RSS software is capable of displaying RSS feeds even if the DTD is unavailable, or have a backup copy cached locally for your parser to use in the absence of the specified DTD. If you are a content provider, either update your feeds to point to another copy [web.archive.org] of the DTD, or accept the fact that your feed may not be available through feed readers that don't have a backup plan in the case of a missing DTD.
It is interesting that they're advising people to use the archive.org version instead.