I heard about GIMP 2.7.3 (released 2011-08-22) and its long-awaited single window mode from LWN recently. It read "[v]ersion 2.7 [..] wont hit most distro repositories for a while" quoting Linux Journal. That got me interested. Most distros? Not Gentoo: I updated the ebuild to 2.7.3 today. Once you unmask it, you can emerge it. Please report problems with it on bugs.gentoo.org as usual. Thanks! If the next weeks go well, it could get unmasked soon.