When you enter the park it's like you died and went to heaven but then you realize you're not because of the thousands of people around you pushing and shoving. That is the only con at Keukenhof, everything else is wonderful. You get to walk between tulips, daffodils, hyacinths and many many more types of amazing flowers. You can also purchase bulbs and flowers at the park. Make sure you get your tickets online because the line to purchase them there is a mile long.
Keukenhof Gardens, just an half an hour bus ride outside of Amsterdam, are worth a visit, even on a rainy day like the one I visited on. They're only open for two months, from late March to late May, but if you have good timing check it out! I wasn't that into all the flowers at first, but its a truly beautiful park and when you think tulips and the Netherlands, you're probably thinking Keukenhof . http://wheninespana.wordpress.com/2012/06/08/queens-day-weekend-utrecht-and-keukenhof/