I used to be of the opinion that Debian stable was too old, that its packages were outdated. Then I realized that I only need Emacs 24 (compile it from source) and a recent browser (both Chrome and Firefox have up-to-date repositories). I've been using Debian stable for over a year now, and I don't regret it. As a student, it is more important that my machine remain break-free that it is that I have the latest version of my bittorrent client.
Out of curiosity do you have issue when running Iceweasel? I had some issue with my IDE (PyCharm) and a few random web applications that just hated Iceweasel. I just self installed Firefox.
I'm not the parent but I've never had issues with Iceweasel. There was a time when the user agent string did not contain "Firefox", but it does now [1] (that might have caused you problems?).
And if you're using wheezy, there are backports to the latest Firefox (iceweasel) packages. I usually see the update on the same day or the day after the official Mozilla release.
I've discovered, between using Arch, Debian, and OpenBSD, that I rarely need the newest version of anything. The only time it has been an issue for me is really at the kernel level, when a newer kernel supported something that an older kernel didn't.
