Hi Marc
I think using a CMS is a no-brainer - 1 page or 1000's of pages. I see you are already using Wordpress - which is good in the sense you have started with a CMS. Whether you need to consider SS or not depends on where your 1 page site needs to go. If it is just a social thing - in my opinion - Wordpress or Drupal will do fine.
However if you are looking to push the boundaries and are trying to support multiple authors, multiple content types. mashup stuff - like maps, videos, image, want span protection, a robust discussion forum (like the one here) + other Web 2.0 stuff, then perhaps you should consider something like SS.
It also depends on whether you wish to become an Object Oriented architect and a PHP programmer yourself or whether you are looking to get things develop.
My sites www.prashanta.com and www.thebigidea.co.nz - former SS latter Drupal.
Hope this helps
cheers