I find it extremely hard to go from dark beer/ale, like newcastle or guinness, to pilsner. But that might be because most pilsners in Norway are really crap.
I feel the same way, except I'm only picky about the first beer, if quality beer is readily available. Otherwise, I just go for whatever swill I can get.
I like to drink light beer - mostly because I'm overweight and when I drink beer I usually drink between 10-30 of them. That many non-light beers is really pushing it on excess calories.