I am a solo traveler and was on Silversea's Silver Shadow for 9 days beginning November 13, 2009, embarking in Barbados. I have cruised on Seabourn several times, so many of my observations about Silversea will be from the perspective of comparing two luxury cruise lines.
The reason I chose Silversea over Seabourn for this particular cruise was for three reasons: Silversea had a generous single supplement (only 125%); the itinerary was the southern Caribbean (only Seabourn's new ship, the Odyssey, is sailing that particular region right now....and their single supplement is 175%), and Silversea still has formal nights in the Caribbean (Seabourn's smaller ships do not). I was in a Vista cabin, on the fourth deck.
Embarkation was very easy. I had come into Bridgetown, Barbados several days early and stayed at the beautiful Hilton. I am a scuba diver and, since I dive only about once a year, I chose the Hilton for its gorgeous views of the Caribbean, and the fact they have an on-site dive shop. I loved the hotel and the diving was great. Interestingly enough, I met a couple, on CruiseCritic, who was also on my sailing and we met up at the Hilton for dinner, and boarded the Silver Shadow together. One of the great benefits of the CruiseCritic message boards is meeting people before your cruise. Especially if you are traveling solo, it's nice to have some "friends" right off the bat!