Just from my experience.
Fire Breath is really nice in this matchup. Stops a lot of Ike's approaches, including quickdraw and if you can keep yourself spaced you can hit him out of his aerials with it sometimes. Flying Slam is a good counter to counter if Ike is being predictable with it.
Fire Breath and Bowser's quick tilts seem to work pretty well in shutting down Ike on the ground. Ike's aerials have surprising range (much greater than Bowser's) and priority. The way I see it Bowser is better on the ground and Ike is better in the air. Ike's jab combo is still really effective though.
If the Ike throws out his laggy moves recklessly or has bad spacing you can shield fortress him to death, Bowser needs to play this one really cautiously, but so does Ike.
It seems reasonably even.
Only video I have is this old thing
http://www.youtube.com/watch?v=KLhUKs00eHo . The second match is closer but we both could have played better.