Lala.com. For the users of Lala.com, the problem was a little more complex. The short-lived online music service, which allowed users to cheaply purchase streaming access to music, was bought out by Apple in December 2009. Users who had existing credit with the service were allowed to transfer those credits to iTunes, but any purchased streams were gone for good. No provision existed for, say, allowing legal MP3 downloads of the purchased streams. (Blame the thicket of restrictive licensing agreements that automatically spring up around any online media service and the fact that music isn't really "purchased" online but merely licensed.)
The fate of Lala brings up an interesting question. Given how many media services are offering "rental" rather than "purchase" models for their offerings, at what point will people feel an entitlement to that data as theirs? And given the voracity with which companies can gobble each other up, how willing should people be to pay money for access to something that could dry up overnight?
These are not questions that have set answers, since they deal with conceptual changes in the nature of the services people consume, and are heavily affected by the reputation of the company in question. For example, few people expect Amazon to go out of business anytime soon, so there's not the same hesitancy about buying books on the Kindle as there would be about streaming music from a fresh young startup.
Look for these features
If you're currently deciding whether to use a specific Web service, it helps to know how it will handle your data and if it can provide you with ways to rescue your data or move the information offsite. There are several things to look for.
Data is available in open formats for easy download. The best sign that a website or service has the preservation of its users' data in mind is the ability for users to make a backup copy of their data through the service itself. If there's no back-end tool for downloading copies of your content, you may be forced to scrape the data manually, so anything that saves you the trouble of having to do so is worth noting. The wiki-creation site Wikia.com, for instance, lets you save whole wikis or individual pages into plain text files either for archiving or offline editing.
Interestingly, Google has been making major strides in this area. When it recently started beta-testing its Google+ social network, it added extensions to allow personal data (contacts, circles, etc.) to be exported via Google Checkout. The real test of such a feature, though, is how useful it'll be to transport your data into other services.
Data tools are provided by the service or third parties. If you don't have direct access to your data through the service's own Web interface, the next best thing is an application that can pull that data for you via one of the service's APIs. You might have to do some programming on your own to take advantage of those APIs, but it's a good idea to look around first -- someone else out there might well have done that work for you and made the results freely available.
Andrew Reichman, principal analyst at Forrester Research, says any service you use should be considered proprietary, even if the provider of the service advertises its own exit strategy. In other words, take any claims about data portability with a hefty chunk of salt. "Even with standards [for data interchange], you are still at the mercy of the administrators and policies of the company operating the equipment on your behalf."