[kibwen]

Rust has much less emphasis on CTFE than D, and instead has a very extreme focus on zero-cost memory safety (and, following from that, a concomitant focus on easy concurrency).

D also owes more of its ancestry to C++, while Rust takes a lot of its inspiration from the ML family of languages.

Both languages are gunning to appeal to C++ programmers, and they're both worthy in this regard depending on your use case. The C++ pie is more than big enough to let both languages thrive independently (and their underlying philosophies are different enough that I expect very little overlap between their communities).