I'm still using boost smart pointers, but it's on my todo to replace them with the C++11 ones.

Also, one part of my code uses boost::hash, but I plan to replace that with std::hash.

I've moved away from boost's assert as well, since I have my own assert code.

Other than that, I'm still using boost::filesystem, and recently needed to (unfortunately) add boost::any.

Boost has some nice items which I have used in the past but many of them have been moved to C++11 as Simon mentions above. For a game I generally try to avoid external dependencies as much as possible but things like: Boost serialization, ASIO and filesystem are pretty tempting when you need something to get a job done. Of course there are other standalone libraries which can be used instead, some of them are preferable in some ways also. It is really all a case of what you need, what your environment is like etc. Some examples:

ASIO- far beyond networking, I've used it to write daemonized multicore event driven data processing systems that were freaky scary but thanks to the ASIO framework it was just a matter of plugging in some custom event sources and then the processing code.

Serialization- well, I prefer a stand alone library I found but when you are in a hurry and can't sit down to write a custom serialization system it is a good enough stand in.

Filesystem- easy enough to replace, but time consuming. I wish this had made it to C++11 but it didn't, so do it yourself of use Boost.

Most of the other libraries are more special case and in many ways not really that useful. Exceptions such as context and others exist but are specialized to certain needs, signals(2) is something nice looking but for UI I use QT and would be unlikely to use signals in a game engine as I generally refer immediate mode UI's instead of retained.

Anyway, it is dependent on your needs at any given time if Boost is justified.

Im not running C++11 so theres a few libraries Im using ontop of my head and loving:

Serialization: I use this for loading/saving my custom asset files. Extremely easy to serialize/deserialize nested structs of data, and amazingly supports all the stl containers. The only downside is that it is NOT a header-only lib

Foreach: simple and I love the syntax. Awesome.

Bind/function: I use this for registering user callbacks for my input module.

Hash: I have scenes, nodes, meshes, etc reffered by name and I match them by the hashed names

I guess C++11 would have the greatest impact on how much of Boost I'd use.

I'm not running C++11 myself. At least, I don't think I'm running C++11 (using Mac OS X 10.6.8, Xcode 3.2.6, gcc 4.2.1). Given that I want to eventually support Windows, Mac, and maybe iOS, is C++11 supported in enough compilers to be used for production code?

I'm specifically getting Boost for signals(2) which I'll need for my UI code and for certain other things that need to generate events. For example, I want to be able to attach events to specific frames of animation objects. I'll probably also start using unordered_map since I have a lot of things I keep in maps and refer to by string IDs, and I don't need the sorting.

At least, I don't think I'm running C++11 (using Mac OS X 10.6.8, Xcode 3.2.6, gcc 4.2.1).

You have C++11 available. I don't believe it is enabled by default, though.

I spent a while in the CMake articles making sure it is enabled, by default it is not. As a note though, I'd be curious why you have not updated to the newer Xcode? The transition to Clang is quite worth it, faster compiles usually and usually considerably better code generation.

At least, I don't think I'm running C++11 (using Mac OS X 10.6.8, Xcode 3.2.6, gcc 4.2.1).

You have C++11 available. I don't believe it is enabled by default, though.

Given that I want to eventually support Windows, Mac, and maybe iOS, is C++11 supported in enough compilers to be used for production code