i'm due for mine too, i'm actually at 800miles, a little over but its been in a warm garage for the winter. anyway, i know that the dealer told me that kawasaki will be more inclined to honor any warrenty issues if the first service is done and recorded by the dealer, so i will take it there for that, i was quoted around 130$ for the service, this includes hourly rates, and shop materials. oil etc.
on a side note, a buddy of mine just had his CBR 600RR serviced and he said they do a ton of stuff, like reset gear ratios, and things of that nature,said it felt like a different bike when he got it back. his cost about 200$ maybe honda does things different. who knows.