Standing in line, wasting precious first-day-onboard time to nab a hot shore excursion, is rapidly becoming a relic of the dinosaur age. Royal Caribbean is the latest cruise line (Princess and Celebrity already have the feature) to allow passengers to book shore excursions not just in advance but also online. It's easy; simply click on shore excursions, pick your destination, browse through the possibilities and book it. You get confirmation via email and your shore excursion tickets are delivered to your cabin on the first day.
The only other requirement besides a credit card (and paying in advance for shore excursions is a nice way to reduce the post-cruise sting of onboard charges) is you must have your cruise booking number. That means you can't buy your excursions until you've paid for your cruise and received your documents, typically a month or so prior to departure.
Change your mind once you've reserved? Royal Caribbean, which just launched its feature this week, says you can make changes up to ten days prior to embarkation. After that, you have to make them in person (which defeats the purpose cause it means you have to queue up at the ship's onboard shore excursion desk). The company also says that it reserves some spaces on each tour for Luddites.