According to the sales guy all the apps come via apple and itunes so there shouldn't be any need for virus software.... not convinced by this.
ie. How does it work when installing Skype for ipad directly to your ipad?
That explanation wouldn't convince me, either. But apart from the fact that Apple curates the applications offered in iTunes, there's a more fundamental reason that the iPad is not (as) susceptible to viruses and malware as other platforms. You may hear people talk about the iPad's "walled garden" or "closed" design for applications. What this means is that an app and all the data it uses are segregated from the rest of the operating system. Therefore, it is simply not possible for an app to contain code that "escapes" from the application and impacts other apps or the operating system.
This is a very good design if your highest priority is eliminating virus and malware threats but it does have downsides. For example, there is no "common" file system accessible from multiple applications. That means that if you have a single document, only one application can modify that document. Another app has to work with its own copy of the document. Thus, it is sometimes problematic to use multiple applications accessing the same data. You will see this most obviously if you have a photo or a PDF and want to use different apps with that data. Changes by one app will not be reflected by the other unless you export the document and then re-import it to another app.
So the bottom line is that you don't have to rely just on the fact that Apple imposes rigorous tests on apps available in the App Store. The software architecture of iOS provides its own barrier to malware. Of course, it's possible to circumvent these protections to some extent by jailbreaking an iOS device. And that is one reason Apple tries so diligently to prevent jailbreaking. But even then, the underlying architecture of iOS is a pretty good defense.
P.S. In response to another question above, the same logic applies to picking up a virus via a browser. Any malware you might download from a browser cannot "escape" to affect the operating system.
