I have installed the x86 Image of Android 4.2.2 on Windows 8 x64 with 768MB RAM allocated and got it running in "fast mode" due to my CPUs VTx, and rendering the UI menus is fairly fast, close to 60 FPS (although most of the time it's more like ~50 FPS, and this is on a Core i7 2600), and I've also checked the "Use Host GPU" box.
I figured the GPU commands do get forwarded based on a simple fact, the GLES2 capabilities are more in tone with my desktop GPU (like say 32 max texture units). However, the framerate in a GLES2 app is ~2 FPS and it's not even based on complexity. Anything I throw at it, even an app with 10 drawcalls still performs at around 2 FPS, so there's must be something really weird going on as simply forwarding the GL commands to my GPU (a HD7850) should provide a fluent 60 FPS.
There might be several issues that result in poor GLES2 performance:
Do you have Intel HAXM (Hardware Accelerated Execution Manager)? It really helps with the emulator performance and speed. It can be downloaded via Android SDK Manager. After downloading it, go to SDK/extras/intel/ and install it.
Do you have the latest video drivers? If not, you should perform an update.
How are you launching the android emulator? I am asking this because if you start the avd using the command line, you need to copy 4 dll files from sdk/tools/lib to sdk/tools. The 4 files are: libEGL_translator.dll, libEGLS_CM_translator.dll, libGLES_V2_translator.dll, libOpenglRender.dll. If launching from the Virtual Device Manager, you don't need to perform step 3.