I personally see no reason to introduce a rimfire division in USPSA. One of the things that makes our sport relevant is that we MANDATE full power (or almost- full-power), large caliber handguns. It is the driving force, our foundation. Take that away and you have lost the whole point. For our sport, .22s are really training tools. The whole point of USPSA is to utilize large caliber handguns for practical purposes, purposes that a rimfire is simply not suitable for due to its fundamental lack of power.
Now, having said that, is there a place for a segment of our sport to use the advantages of the rimfire, (the lower cost of both ammo and guns, light recoil and less noise)? You bet. I use .22 pistols and rifles constantly in my training now, both for myself and others. But I simply can’t imagine why we would want to incorporate them into the matches we now run?
Incorporating a rimfire division would require events to be designed so differently that what we now call Practical Pistol would be unrecognizable. Matches are supposed to provide a platform for the development, training and testing of techniques and equipment that are suitable for PRACTICAL USE. Now I’m sure that others will have a different view, but I feel we have already reduced the VIS part of the DVC equation enough. Factory rounds are now too hot to use in a match because they kick too much. Now we add .22? I honestly feel it would really hurt the sport!
History Note: DVC, the Latin motto Diligentia, Vis, & Celeritas, meaning accuracy, power, and speed, are recognized as the quintessential elements of IPSC, used in balance, and they are the foundation of the sport.

Our club in Mesa Az., the Rio Salado Sportsman’s Club, is Mecca for practical shooting and we have an excellent .22 match every fourth Sunday of the month that caters to the new and inexperienced shooters. It is fantastic. It exists in hopes of getting the newbie some experience with match pressure and the process of competing. This separate type of event is the natural place for the rimfire and I recommend it to everyone who wants to get into this sport.
At some point we should recognize that USPSA already has a division for everyone who wants to shoot this sport. I don’t think we need or want to add another division just to make a home for an unsuitable category of guns. I don’t want to watch snails race, or ostrich flying contests or who can hold their breath the longest either. And in USPSA matches, I want to shoot large caliber service type pistols in courses of fire that reflect the practical use of such guns.
BTW, I love .22s! Have lots of them and take them to the range all the time. I just don’t want to shoot practical pistol with them. Maybe what USPSA needs is an organized type of introduction / training program for our sport. I would certainly recommend the rimfire for that!
Rob