It appears that Bioshock 2: Sea of Dreams will have a multiplayer mode, and will be available for the PC,PS3,and 360.
The following is a recent posting on gamasutra.com’s job listings section:
Leading multiple engineers within a proven team to design and build a network frontend and backend support for an action-packed AAA multiplayer title
• Advising engineers on how to properly architect their systems for optimal multiplayer support
• Extending and enhancing Unreal Engine 3 with proprietary networking tech to address gameplay, performance, platform, production, tools, and QA needs
• Interfacing with Microsoft, Sony, and other providers for matching-making and other services
• Working with the Technical Director, Lead Programmer, and IT Director to plan and execute major changes to core technology or backend services
• Responsible for delivering a robust, scalable, and responsive multiplayer gameplay code and backend services for the PC, PS3, and Xbox 360 platforms
The BioShock team is betting big on multiplayer and plans to stay at the top of the charts– we’re careful about the problems we tackle, innovative in our approach, solid in our implementation, and we polish the heck out of everything we do. Right now we’re looking for an exceptional individual to direct the development of this multiplayer experience through a combination of leadership, design, coding, and daily problem solving on the gameplay networking and backend server components.
http://www.gamingfront.net/story-180-.html
This is the same source who said a price cut for Wii so take it with grain of salt altough it could happen u never know.