I hate trying to recommend a bike, because everyone has different wants/needs/skill leves/etc... I have one friend that started on a $7000 GSXR 750 and he's absolutely terrified of the thing, it ruined any chance of him becoming a good rider. I started on an old CBR 600 and absolutely love it, put on about 9k miles a year. Another friend started on a Yamaha R1, again, he loves it and puts on over 5k miles a year. It all depends on how familair you are with two wheeled transportation, the roads you travel, your outlook on riding (please, for the love of God, don't buy a bike to pick up chicks, you'll end up in the morgue soon enough) , and your ability to adapt to the completely new world of riding on a bike.
Cars don't see you, animals still don't care where they run, and potholes are impartial. It's absolutely insane to ride bikes, but dammit, it's fun.