If full and accurate keyboard functionality in the guest is important to you, let me share my experience as a Parallels user from the beta days through build 5584.
My overall opinion is that such functionality has not been their top priority. In fact, most of the keyboard-related changes I have seen tend towards emphasizing the presence of OS X within the guest as much as possible. The remapping of Command-C and friends to the copy, paste, etc. functions is a prime example.
I use a windows keyboard, no less, and yet the context menu key has been broken for as long as I can remember. (See
http://forum.parallels.com/archive/index.php/t-12848.html for example.) Sure, the right windows key remaps to a context menu key, which is great for some people. Heck, the majority of users use a Mac keyboard and need that remapping to have a context menu key at all. But from my perspective, instead I see one dead key and one mislabeled key and no options from Parallels to change that. Worse, that fact's been staring me in the face almost every workday for the last year, now.
Even before the change we're discussing here, to get the expose keys and command-tab to pass through to the guest instead, you had to change an OS X system preference in Universal Access, of all places.
I can understand their perspective. The biggest market is probably people who like OS X but are stuck using some Windows app or another. Most of them probably want to be as close to OS X as possible, even in the guest. But some of those very applications that tie them to Windows/DOS (and thus to Parallels) can be keyboard intensive, so this is a sensitive issue. I've waited patiently for change, made requests and observed others making theirs, and nearly two years later haven't seen satisfactory progress in those directions (though I'll say in a heartbeat they've made great progress in other areas).
For reasons like this, I just recently tried a demo of VMWare Fusion in Leopard. It's too early to comment in general, but I can make some comments related to this topic. Without having to enable access for assistive devices in Universal Access ahead of time, *one* checkbox in *Fusion's* preferences let me control whether the guest or host received the command-tab and expose keys. (You're stuck if you wanted one but not the other, though.) Later I plugged in my Windows keyboard, let OS X identify it, and launched Fusion for round two. My right windows and context menu keys finally function as printed on the keyboard. It's a small thing, but it's a small thing that matters to me.
I could say that I'm two years closer to Parallels offering similar choices and ease of use in this area. I could also say I've waited two years too many.
