If I get a gift of the game do I still get the pre-order stuff?

[MaximumSquid]

Pretty straight forward. . .

Friend uses his credit card and gift wraps me the game before release

Do I receive the bonus items?

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[japanimater]

Yes, since I gifted Worms:Reloaded to a friend and he still got the soldier hat.

[in.meinem.turm.]

Pretty straight forward. . .

Friend uses his credit card and gift wraps me the game before release

Do I receive the bonus items?

-

You will recieve the bonus-item (visor) and you will be able to unlock the other items in the game.

[Stevontoast]

Yes.
Gifted games can receive pre-purchased bonuses.
Happened with L4D and Worms.