I've been sitting on the fence with the game pad and Naga for a while but after listening to your show, I went out and got a Naga and Nostromo.
The Naga is a bit to get used to but it is brilliant. If anyone else is pensive about it, just do it. It may take a while to get used to but once you do...! If you're going to use it offensively, I recommend spending some significant time on a target dummy to try to build the new movements into muscle memory. The first character I tried it on was my priest and I spent some time running around Ironforge popping shields and healing everyone on the fly with mouseover macros. Oddly, I'm having the opposite experience as you, Stump... I find it a natural fit for healing but DPSing still feels odd. Nonetheless, I haven't been this giddy about a product in a long time. It's really, really cool. Words can't express how awesome it is.
As for the Nostromo, It is really comfortable and fast. It feels like an extension of your hand and requires very slight finger movement. While I loved the product, I reluctantly took it back and exchanged it for a G13 because I wanted more keys. State changes with multiple keybinds just mess up my muscle memory, so I wanted more physical keys. I'll take slightly less comfortable, slightly slower, and a little more movement in exchange for more utility but I chock that up to personal preference. Compared to the Nostromo, the G13 feels pretty much like a small keyboard. If I was playing a first-person shooter... Nostromo without a doubt! It is a terrific product and I highly recommend it.
On a side note, with the default configuration having the movement on the thumb of the game-pads... I didn't find it as awkward as others have reported.