Personnally, I don’t really worry about it:
The current gcc’s version is labled as a prereleased version, but I’m pretty sure that devs have backport features from more recent version of gcc.
The problem here is that on point in the release cycle, they have to fix version numbers so sometime they are oblige to release a prerelease version (ex: firefox 3.0b5). However, after version freeze, they can still fix bugs. So the version number will stay at a prereleased version, but stability wont be a prerelease stability.
What may happen in the future:
A: gcc will be updated to a stable version after devs have make sure that the update it wont cause system unstabilities.
B: They will backport bugfixes and features from the stable releases.
You may search with: Webpin
To find if a third-party repo has a more recent version. But it wont be “supported” by the official developmental team.