I would definitely reccomend using a controller, but to be honest it's all personal preference

Kawa used a keyboard for the longest time, he might still, and he was competitive in the 2010 supercross series.
MY opinion:
X360
pros - throttle/brake/steering control, if you can get it figured out, you can get the triggers on seperate axes.
- can press more than 3 buttons at a time (not that you really need to

)
- feels much more natural than a keyboard
cons - the joysticks can be a bit touchy and you may need to manually sset the deadzone in your config file (which i had to do=/ )
- takes getting used to, in the whoops mostly i have noticed.
- uses a USB port (only have 3 on laptop, usb hub broke

) <----joke

If you get a wireless one, you may have to buy an adapter, which still may not work, my brother bought one, still doesn't work.
keyboard
pros - ask me in another 6 months
cons - it's a keyboard...
for recording, I personally use the script for avi recording (it's stickied in the "scripts, software, and other stuff" thread) as fraps drops my fps to around 3, no shaders or anything enabled..
video editing, again, all personal preference, I use windows movie maker because it's free

but some people use Sony vegas pro, or some other thing...