Two of the biggest stories to come out of E3 2015 were the long-awaited reveal of Fallout 4 and Microsoft's announcement of backwards compatibility for the Xbox One. Now, we've been given some more information on how the two are linked.

Anyone who pre-orders Fallout 4 for the Xbox One will receive a downloadable copy of Fallout 3 to tide them over until its release. This promotion was mentioned during E3, but it's now active for anyone who is ready to pre-order from their console or via the Xbox website. It's expected that all purchases of the game, whether physical or digital, will qualify.

The code for Fallout 3 will be delivered within 7-10 days, but you'll only actually be able to play it on your Xbox One once the title is added to the list of supported Xbox 360 games. At present, we don't know how long that will take, but it's expected that more games will be added on a regular basis.

Backwards Compatibility is currently being rolled out to Xbox Preview members. Users who currently have access to the feature can play a selection of titles, largely from first-party developers like Rare. Microsoft announced at E3 that over 100 titles should be available by the time the functionality is officially implemented later this year.

Hopefully, Fallout 3 will be added to the list sooner rather than later, as fans will want to play it as a preface to Fallout 4 rather than receiving it alongside the new installment. This sort of pre-order bonus could be a huge boon for Microsoft, but it's clear that the specifics of how it will work in practice are still being ironed out.

Rainbow Six: Siege will also adopt a similar strategy, offering both highly praised Rainbow Six: Vegas games to anyone that purchases the title for the Xbox One. The question is, how will Sony retort to Microsoft's plan to give multi-console owners a reason to play new releases on the Xbox One as opposed to the PlayStation 4.

Remasters and remakes like Uncharted: The Nathan Drake Collection and Gears of War: Ultimate Edition still dominate the release schedule for new consoles, but backwards compatibility could well disrupt that trend. Microsoft made a power play by introducing the feature to the Xbox One, and it will be very interesting to see how Sony responds.

Fallout 4 is set to release on November 10, 2015 for Xbox One, PlayStation 4 and PC.