Really? In Spaces, I can grab a window with my trackpad and then hit my hotkey to go to the next space. In Gnome on Ubuntu, I have to right-click and hit "move to workspace", and in apps with nonstandard widgets (read: Chrome), even that doesn't work and I have to go down to the taskbar to do that.
You can do this in most desktop managers for Linux as well, where Spaces fails is how each workspace in managed. In Gnome each workspace acts almost like a new lite session, for example only the applications in the current workspace show up in my task bar (this is optional by the way) and when I alt+tab then only the applications on the current workspace are tabbed through. This works very well because when I switch between different task (say photo editing and programming) I don't want to generally think about what other non-related task/applications are running on my system. In Spaces every workspace is part of a kind of global workspace and there is no hiding of task environments.
The different environments all have their own shortcuts, but you can definitely customize things. Might I suggest awesomewm? It takes about two days of reference back to the man page (keep it up in its own tag ;) ) but after that you generally have the hang of it, and it has far more advanced features for workspaces/tags than the other players, at least the floating WMs.
I've never really liked Gnome much, you might want to try some of the other DEs out there, especially since Gnome is pushing a whole new interface in a few months so you'll have to learn new stuff anyway.
