The Playstation 2 is the upgrade to Sony Playstation.  It is equipped the capability to play Playstation, Playstation 2, DVD's, compact discs and connect to others via modem. The Playstation 2 is marketed to all gamers and has a library of games to include all ages and with DVD player capability it has an even larger market. 

The Playstation 2 is manufactured by Sony.  Software is developed by EA Sports, Sega, Titus, as well as many others. Here are the specifications.  You can buy the Playstation 2 from Best Buy for $200. 

To read up on the history of Sony's involvement in the video game market click here. 

News
Sony poised to lose battle
New Wireless Game Tech Works with PlayStation 2, Xbox and GameCube 
Sony Ships Linux Kit for PlayStation 2

Pros and Cons
The Playstation 2 is nice because of better graphics and quicker more in-depth games as well as the ability to play DVD's.  Video games can also become addictive and interfere with what most people would consider more important things in life. Here is a great article about this concern. 

Product Reviews
Playstation 2
Software

newsgroups
Playstation 2 Online
METAL GEAR SOLID 2

Predictions
I predict the Playstion 2 will remain the dominant video game system for next 2 or 3 years.  After that it's very hard to predict the market because there could be competition from a number of different companies.