But several hours ago in the mobile world congress show they've announced a new mobile version of Skype which let's you make calls under lower networks such as 2G where 3G or other faster connections aren't visible. Now this version will also be more "light" on your phone's battery and memory as well.
Anyway Facebook also seems to be interested in creating a bit similar services to the millions of FB fans all over the world... so in the future Skype may have a bit of a competition as well. The new Skype mobile version according to the developers will run on multiple OS.
Source : this pcmag skype mobile congress news article.