but he could ride a speeder in the first movie? :p
Yes, because that looks pretty normal for the scene. If you look at the cutscene where Luke is on a swoop bike, it just looks wrong to me. It's like he's trying to be some biker gang guy, which just seems jarringly out of place for his character to me. The landspeeders in the first movie were a normal type of transport for the area, like cars are for us.
EDIT: Here's a still from the cutscene in question: http://customstarwars.freeweb.hu/sote/lukeskywalker_dash_rendar.jpg
Maybe it's just me, but something just doesn't look right about Luke riding a swoop bike like that. Maybe it is the seated position of the bike, or the bike's general appearance. It is like it is trying to say "look at me, the tough gang member type" which isn't Luke's personality.
EDIT2: Attached some images. First Luke in a landspeeder - looks fine. Next, Luke on a speeder bike - again, looks okay. Lastly, the image from the link, Luke on swoop bike - something seems off here.
Oh, and I had to log in with Internet Explorer to get the attach button to work. Trying to do this in Firefox (x64) didn't give me any file browse when clicking on attach. Never had that happen before as I've been using Firefox for a long time now.
LOL, I get the opposite impression.
I think he just looks like a guy who enjoys having fun with powerful engines, which is exactly like his personality, and his father's for that matter.
Like father, like son.
Most guys (and some women) who enjoy powerful engines also enjoy a variety of vehicles.