Heyup Rich. I'm afraid I've not really got time to do an 'in-depth' look at how these were done. To be honest, since I'm only just exploring 2D as an aide to my 3D work I'm probably not in the right person to advise anyway. (I'd say Jaquesueusiusd is more of our resident 2D expert

)
As for a quick overview, nothing out of the ordinary really - stuck to the main animation principles of thumbnails first - then keyposes (really only 3 main poses for the listener dude - start middle end) I then positioned those key poses at the right point on the timeline (to get the timing as I wanted it), then worked on the main breakdowns.
That's where it got quite difficult and where the differences between 2D and 3D were really noticable, since, in 3D the breakdowns are done for you (whereupon you just tweak, or if you no likey, you can then go about changing things) Whereas in 2D you have to think about every point of the character, what it's doing and where it's going to! That part gave me a headache and made me admire 2D artists all the more... (It also changed the way I'll be aproaching 3D I think)
As for software - I think the name of the thread kinda gives it away... my first 'Flash'