#3 Expecting 411 information and 911 (emergency) services
One of the most important "Gotchas" is that Skype cannot call 411 information or 911 emergency services and know where you live to send emergency services. Because Skype is not intended to be used as a primary telephone provider, it is also not intended to have or support 411 information and 911 emergency services, nor should you consider that it should. Skype was designed as a supplement to local and long distance service, and was never designed or advertised to replace it. The lack of these 411 and 911 services are the major reason why Skype is not a primary telephone service.
#4 Expecting Skype to send or receive faxes
I am often asked whether Skype can fax. The answer is "No", unless you consider file transfers a form of faxing, I do not. This is where Skype is not like an analog telephone call that can send the fax negotiation tones to send and receive faxes. If you want to send faxes you will have to use a regular telephone line or VoIP service that supports faxing with a fax machine or a solution like eFax. Do not expect Skype to be able to send or receive traditional faxes anytime soon.
#5 Expecting support
Remember, Skype is free. With free there are some shortcomings, one of which is a lack of real time support. I am often asked for support from the Skype community and I unfortunately have to turn many down and tell them to post a thread on the Skype Forum. I also maintain a forum, but ours is more for solution type questions than general support, but we do try and answer what we can. To get Skype support, use the 'Help Menu' and select Help, FAQ, 'Getting Started' and it will launch your web browser and provide relevant webpages or send you to the Skype Community solution. Staffed support with real people costs money, so to keep Skype inexpensive, self-service is a necessity.