If you are unlike most BlackBerry Enthusiasts and are still running a stock version of BlackBerry 10, you may have received a small update to BlackBerry World. There is no changelog with this one, so you are just going to have to update and find out what enhancements it contains, if any.
At least from my experience, It seems it may just be a few cosmetic changes and a few optimization boosts here and there. Searches seem to populate a bit faster and the updates tab is always visible in the "My World" section. As with any app, make sure to check for updates often from BlackBerry World often to make sure you always have the latest and greatest versions of all your apps, including BlackBerry World.