Whats in the professional edition vs standard? (Hitman Absolution)

Agency Gun Pack

Video of making game

Digital art-book

Description from Steam, yep.

The Professional Edition includes:

• 72-page Artbook
• Making of video
• Agency Gun Pack DLC including:
• Upgraded silencer
• Laser sights
• Agency Jagd P22G: A modern top-tier pistol
• Agency HX UMP: Powerful high-caliber SMG
• Agency SPS 12: Brutal semi-automatic shotgun

Some extra fluff like equipment and artwork or something.

The Professional Edition includes:

72-page Artbook
Making of video
Agency Gun Pack DLC including:
Upgraded silencer
Laser sights
Agency Jagd P22G: A modern top-tier pistol
Agency HX UMP: Powerful high-caliber SMG
Agency SPS 12: Brutal semi-automatic shotgun

Actually there is: Look at this.

72-page Artbook

Making of video

Agency Gun Pack DLC including:

Upgraded silencer
Laser sights
Agency Jagd P22G: A modern top-tier pistol
Agency HX UMP: Powerful high-caliber SMG
Agency SPS 12: Brutal semi-automatic shotgun

You'll probably just get the Agency DLC and making of video if you're buying it digitally

The Professional Edition includes:

a 72-page Digital Artbook
A Behind The Scenes "Making of video"

"Agency Gun Pack" DLC, which includes an upgraded silencer and laser sights and the following exclusive weapons:

Agency Jagd P22G: A modern top-tier pistol
Agency HX UMP: Powerful high-caliber SMG
Agency SPS 12: Brutal semi-automatic shotgun

The pre order of it would give you hitman collection also

Edit: Looks I late O.o , when I entered there was no comment XD

'HITMAN: ABSOLUTION PROFESSIONAL EDITION features a premium hardcover Art Book with a foreword from Game Director Tore Blystad, and an exclusive behind-the-scenes “making of” video, all packaged up in a clamshell box that looks as sharp as Agent 47 does in his suit, the Professional Edition is the ultimate way to experience the living, breathing world of HITMAN: ABSOLUTION.

HITMAN: ABSOLUTION PROFESSIONAL EDITION also includes advanced access to a range of in-game Agency Weapons, giving the Original Assassin a deadly edge over his enemies from the outset. The Agency Jagd P22G pistol will suit the silent assassins, whilst the Agency HX UMP SMG and the Agency SPS 12 semi-automatic shotgun will give Agent 47 the power to fight his foes head on.'

Just a quick heads up, those weapons are not usable in single player.