After all the questions about the shooting games, I thought we should post links to the disciplines that we shoot. There are huge differences in the two.
International Defensive Pistol Association
IDPA is supposed to be geared toward concealed carry. You have to start with your pistol concealed by a vest, shirt, or coat. They have strict rules regarding equipment and gun modifications. You have to shoot targets as you see them while shooting around a barricade, or near to far if out in the open. Stages are usually 12 rounds or less, but can be as many as 18. You have to shoot a stage exactly as described in the course of fire (COF). You are scored on how long it takes you to shoot a stage and then you have time added to that raw time for each point down you are on a target. It's fun, but the tactical chipmunks bow up and start acting silly whenever they perceive something as being "gamey" or "USPSA like". A shooter was disqualified from this years IDPA Nationals for "Gaming".
United States Practical Shooting Association
USPSA is like a video game. It's not uncommon to shoot stages that are over 30 rounds. It's up to you to solve the shooting problem and usually can shoot a COF however you choose. You can use race equipment like the belts, holsters and magazine carriers Catfish and Pimp Daddy are wearing in the pictures. In recent years USPSA has introduced a production class, where you can shoot a stock service pistol and you shoot it out of a practical holster, not a race rig. They also have a Limited 10 division where you can only load 10 rounds in each magazine. You can shoot your single stack 1911 in this division and not have to worry about the low capacity disadvantage. You can also plunk down $3000 to $4000 on a race gun like the one Brad just got.
There is no pseudo tactical bull sh!t in USPSA. Just whip it out and shoot it as fast as you can. You are scored on the raw time it takes you to shoot the stage, and you get points for your hits on targets. An A is worth 5 points, B's and C's are worth 4 and a D is worth 2.
Both are fun and both are trigger time, but most of us here think that USPSA is more fun. Overall, the level of shooter in USPSA is much better. People that dominate their local IDPA match can show up at a USPSA match and find themselves finishing mid pack after shooting a very good match. This has driven all of us to step up our game and get better. We are all shooting better and faster than we ever have.
My advise is to shoot both. More shooting = more fun. You can find a local club using the web sites.