Regardless, there must be a good number of such users, to encourage AOL to develop a plugin that enables their users to collect mail from Yahoo!’s email service, a plugin which launched late last week.

Inline with AOL’s recent strategy at the AOL.com home page to embrace and integrate third party content and services within their own properties, Yahoo’s messaging behemoth is now available – albeit as message previews only – within the AOL Mail interface. Users can then click through to their corresponding message at the Yahoo! service.

It’s all kinda, um, underwhelming and the kind of feature that should have been there all along; an indictment of the ‘data prison’ strategies employed by web’s largest properties.

Data portability is a subject I’ve written about many times here at Web Worker Daily, notably with regard to the portability of email data trapped within services such as Hotmail, Google Apps and Outlook…though fortunately (as these links illustrate) each of those services has a third-party ‘jailbreaking option’ to liberate your data.

With much of our personal and professional data now residing ‘in the cloud’ and on remote services, it’s ever more important to press for the ability to export and import data from any service – and insist on the use of standards where possible. I’m sure that the product manager for AOL Mail has come across the IMAP and POP email protocols. Perhaps offering such capabilities by default can weaken the retention of a customer, but its possible to mitigate this by offering data portability or export as a premium option and actually competing on design and features, rather than crippling a service.

Services such as Dopplr and del.icio.us have long had export features baked in – making this central to a service’s design philosophy illustrates a respect and value for the user that is likely to ensure a degree of loyalty.

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