I've had the opposite experience. For green-field applications, it's far easier to write the application in C++ than Java & meet the latency requirements. Java requires far too much tuning, where as C++, from the get go, you can generally just glance at the code and have a good idea of the latency.

We're currently fighting a Java app that in general has decent latency (10s of usecs), but has outliers of greater than a second when GC kicks in. We don't have that issue with the C++ components of our trading system.