I can't remember the last time I was so eager to use a new website/service. Was it Gmail? Anyway, tomorrow CastleGarden.org opens up and I can't wait to see what they're going to do. I hope it will be similar to the Ellis Island Passenger Arrivals site, which I've only played around with (because all of my ancestors immigrated before 1892).
Even if I don't find any new information, this site has been long overdue for the genealogy community. Yes, there are books about New York passenger arrivals, but it can be a chore to search a paper index for every conceivable misspelling of a name. Ancestry.com has done a great job with their immigration database, especially with the New York arrivals having a soundex search and images of the passenger lists, but their subscriptions are a little pricey and that database is not part of AncestryPlus in libraries.