A few months back Sony updated their PSN TOS/User Agreement presumably due to the PS3 OtherOS removal, and today TheSixthAxis.com (linked above) spotted another update that pertains to the upcoming PlayStation Plus service which arrives next week.
When you hop online with your PlayStation 3 or PSP console next, the PSN Terms of Service update you will be asked to agree to states Type 2 content (outlined below) may be unavailable if you don't renew your subscription immediately at the end of each period.
Essentially this means your PSN and PS1 games, PS3 and PSP Minis and PlayStation 3 downloadable content may become inaccessible if you don't keep your subscription current.
To quote: "There are two types of Subscriber based downloadable content, split neatly into those that you can re-download after your subscription ends and those that you can't.
Type 1: Premium Avatars and Themes, which, so long as you download when originally available you can re-download after you end your subscription.
Type 2: PSN games, PS1 games, Minis and "Premium Game Elements" which we assume is a fancy word for DLC. This, as you'd expect, will no longer be accessible for use after your subscription period expires, even if you downloaded it before expiry.
The PS3 will turn on automatically every 2 days to check for system software, game patches and game demos. Firmware updates won't be applied until you've accepted the terms."
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