On the other hand, many Gmail users have no qualms about leaving their entire trove of mail on Google's servers -- even though both POP3 and IMAP connectivity exist for Gmail, making it not only possible but easy to keep mail local. It's easy to get into the habit of unthinkingly trusting Gmail to always be there -- at least until the next network outage or Google cloud failure.
Practice making local copies of the service's data. If a site has a way to allow you to make a local copy of your data, make a practice run. Step through the process of creating a local copy of the data and see how difficult it is -- how many steps are involved, are third-party tools required and so on.
Also be warned that the process could change on you without warning, so you should take a full review of the process every so often or whenever you get word about major changes to the service.
Keep an eye on what third-party apps are being introduced or removed. If you're depending on a third-party app to help you keep copies of your data, keep in mind that apps can be fickle as well. That app you downloaded six months ago might have since been blocked by the service in question -- or there might be a replacement or even a new (and superior) substitute. In other words, keep up to date and check to make sure your backup mechanism, whatever it is, still works.
Most people don't think much about the inherent closed-endedness that goes with using proprietary Web services, simply because they offer so much in return. That closed-endedness -- and the difficulties involved in porting your data back out -- is becoming increasingly problematic now that such services are so common.
The sad truth of the history of Web services is that any site can disappear, given a long enough time span. But even in the face of such a history, most proprietary Web services still skimp on providing tools to make it easier for users to leave. And why wouldn't they make it difficult, when they have a vested interest in keeping their users? Give people a way to easily switch to a competitor and you've chipped away that much more at the advantages you hold over them.
On the other hand, those who do offer such tools have another advantage: a level of trust with their users that their competition might not have. And given that trustworthiness is becoming a Web currency at least as valuable as ad dollars to some people, it's in any Web service's long-term best interest to start offering those tools. Until then, the rest of us will have to make do with the tools available -- and keep our ears to the ground when rumbling starts. Not if, but when.
Serdar Yegulalp has been writing about computers and information technology for over 15 years for a variety of publications.