Not just uninstall it as you would on a Windows PC with the Add/remove programs applet. No, this eradicates Skype completely, either from a single PC or from a network of PCs.
Why would you want to do that? you may ask. Well, according to the Skypekiller website, Skype presents major risks to organizations through "uncontrollable bandwidth usage, uncertainty as to confidentiality, potential security flaws, productivity issues, etc." Not sure what "etc" means as they don't explain that one.
Instead, read the detailed information about Skype, security and other issues about Skype in the workplace in the Skype security resource center. Also, Michael Gough's Five Reasons NOT to Block Skype on SkypeJournal, in which he says:
[...] Each company is different and should set a policy, evaluate the advantages, support, risks and costs to decide how, if at all, to apply a communication tool like Skype. [...] If you properly secure your clients and infrastructure with "defense in depth," the risk of using Skype is far less than using Microsoft Windows or laptops without encryption.
Setting a policy on usage - as with new-media communication tools like blogs, that makes sense in any organization.
And if you have an interest in VoIP security, there's a great podcast you can subscribe to - Blue Box: The VoIP Security Podcast from Dan York (a regular content contributor to FIR: The Hobson & Holtz Report podcast that I co-host). Blue Box is worth listenting to.