I'd like to have as little portability issues as possible but supports hardware acceleration. The main priority is on PC and having a game run on Windows, Linux and MacOS. Porting to consoles would however be great, too.
Pygame relies on the SDL under the covers so has some added dependencies when going cross-platform. Pygame is arguable more mature and there are tons of examples online.
Pyglet has no external dependencies and is a breeze to distribute with. Pyglet seems more pythonic and has very clean documentation.
I'm going to give the obvious answer here, which is Ogre3D. It's a feature rich and mature 3D graphics engine/framework, written in C++.
It runs on Windows, Linux and Mac OS X and even on iPhone and other devices. There are also wrappers for Java, .NET and Python out there (see: http://www.ogre3d.org/tikiwiki/tiki-index.php?page=Alternative+Languages), so you are even free to choose your programming language to some degree.
SFML is a great framework written in C++. It currently supports Linux, OS X, and Windows. It has bindings to C, D, Ruby and Python. It's also released under zlib/png license.
In comparison to say, SDL, the only downside it has is using window input on win32, rather than DirectInput. It also is not one large library, but a group of them, which allows a more modular approach to which libraries you use :)
libsdl is very portable and supports openGL
You may want to look into Java solutions. LWJGL is a pretty decent OpenGL binding and was used for a number of commercial games already. There's also the official OpenGL binding called JOGL however afaik it's not as mature as LWJGL. You may also want to look at Jmonkeyengine which is a Scenegraph-API/Game Engine. Obviously since it's based on Java there are very few portability issues and with a decent VM (i.e. Suns 1.6 VM) performance is more than good enough for most cases.
Panda3d is a free game engine that works in Linux, Windows and Mac OS X
Allegro will work on Windows, OS X, Linux, DOS and some others.