oh wow diego O_O awsomness!!! you did a really great job^^ and you're talking with a future animator ;D Bam Bam's one is good, you used a right number of frames and so, the animation came good :]
I like the second one too^^it's more difficult to do a running pic but you did it correctely, the back's paws are right (I really like how you did them), the front paws are good too (you did well a frame that came such for me -.-) but I think that you should use another frame(s) because the durungee has to be elastic, if you see better the durungee, you can see that it looks a bit rigid ^^' look at this-->
http://fc32.deviantart.com/fs34/f/2008/290/8/e/running_wolfeh_by_Saske_Italian_Wolf.gif you did it correctely (as I said) but do you see that mine's looks "elastic" ? great job anyway but I want to suggest you this
http://thedreamwolf.deviantart.com/art/Animation-Tutorial-Running-Dog-11317081 it's a great tutorial for animating^^ I used it and I am satisfated of my running wolf ;D