>>6
A lot of what's slated for C++0x (due in 2009, hah) has been in D for years, including proper thread support. D's author also writes a C++ compiler, so he rips of good ideas soon after they appear, including the C++0x proposals.
>>1
That depends where you're coming from. If languages like Python/Ruby/Lisp/Perl are your thing, you won't get much out of D. Despite the claims, D isn't as productive as them. Also, while D's templates are a lot more powerful than C++'s, they're still ugly as hell.
However, if you're coming from C or C++, then D is a very big breath of fresh air. If performance code is your thing, D is a good choice, although it's still a bleeding-edge language with all the associated problems.