We would urge all users of SMF 1.0.9 and below to upgrade to SMF 1.1.1 but we will continue to patch the SMF 1.0 line as required.
I can't seem to find a clear answer anywhere. I may have missed it or my search terms just might not have matched it to decent content. I have three clients whom, for reasons of their own, simply can't upgrade at this time. As this is a shared server environment and, frankly, one that my employees and myself are ultimately accountable for we have a policy that disallows insecure code on the system - within reason.
I'm not too concerned, and surely not concerned yet, but there's going to come a time when you can't really support old code I suspect. No matter how ideal, no matter how important, it simply seems to be unrealistic to expect you to. (Thanks for doing it for however long you can and do do it.)
Is there a set date or condition as to when support for the older version will expire? I have read everything from "for as long as we can" to "forever" I believe. The first is not very specific and the second is probably impossible.
I don't ask to be a pain... Reall... Well not to be a pain to you guys... Instead I ask so that I can poke and prod them into upgrading their themes to 1.1 and moving along or at least tell them when we'll have to insist that they do. As much as we'd like to be idealists and say, "It is your space, do with it as you will" there are more and more laws coming into play as well as more and more people looking for legal accountability and in a shared server environment vulnerabilities are best squished when found.