Also, I didn't mention the updates in parallelism that were added (because they should have come earlier)...but do you think c++ is comparable to a modern concurrent language atm? Worth it over erlang?
Other people may have different opinions, but I don't think C++11 will convert anyone, but people who already have a big time, or code, investment in C++ will find much of their lives much easier. Another indirect advantage is that by moving to C++11, it finally allows people to make a clean break from older, less standard C++ compilers. Wether will we end up with a new state, where people end up supporting partial C++11 compilers, we will have to wait and see.
The parallelism is really just standardising existing behaviour in many cases. People who want to write things like lock-free algorithms are very excited by the atomics stuff, but such stuff is beyond me.
I am disappointed that some more practically useful threading algorithms, like thread pools and such like did not end up in the standard. However they now seem to be arriving as 3rd party libraries.
I think what is going on is that before a threadpool library was '2 steps removed' from standard C++ (as first you had to write, or use someone else's, threading/atomics library). Now they are only '1 step removed', they are more useful.
In modern architectures there are lots of places where you can get way faster, just by organizing your data in more cache friendly ways, or the way the data is layered across registers and memory regions.
You need a language like C++ for these type of optimizations.
One other big advantage of PHP, which I find as time goes by, is (boringly) its broad stability. I first learnt PHP over 10 years ago, and what I learnt then still works now. Web apps are a very small part of what I do, I knock together the odd small one every couple of years or so.
I did do one app in Rails, but when I next came back to look at Rails about 18 months later, it seemed enough things had changed my app broke in various ways. I find I increasingly appreciate a large community, a book or two, and some stability.
Obviously if your day-to-day life is web design that doesn't apply. My day-to-day life in high performance algorithms, and I was using new C++11 features as they got implemented in compilers, and have played with many languages in that area.