GCC now implements the C++11 _language_, but as of yet falls short on the _standard library_.
LLVM now has both. And IMO is a more honest claim to using the word "complete"; confusion over the competing release announcements is not uncommon, and people who want to try C++11 on GCC will be confused when e.g. <regex> never works as expected--it is stubbed out, meaning it won't give a compile error, but there is no implementation.
To be fair, completing the language portion of the standard is an achievement that GCC deserves to trumpet, but the next sentence in their release announcement should have clarified "work continues on the standard library (help wanted)."