Rush Limbaugh, the popular – depending on your politics – radio talk show host, has joined the Podcasting craze, though his Premiere Radio Networks syndication company is eschewing traditional audio delivery methods for the daily show in favor of a proprietary system that supports a paid subscription model.

Podcasting, a term that refers to downloading and transferring audio files to a music player such as an Apple iPod, normally uses Really Simple Syndication (RSS) feeds to deliver content to those who want to listen. RSS is an XML subset that includes a title, description, publication, date and location of the MP3 file itself.

But RSS is too simple for Premiere Radio, which needs to authenticate users against its database of subscribers who pony up $6.95 per month for the “Rush 24/7” service. Instead, the company is using Maven Networks content delivery service to authenticate customers and push shows down to them when they become available, typically a few hours after the live radio broadcast, says Brian Glicklich, vice president of interactive services at Premiere Radio.

Limbaugh subscribers download a small application that runs on their Windows or Macintosh system, enter their username and password and wait for shows to download in the background. “They don’t have to do anything to receive the show, they just get a message when it is ready to play,” Glicklich says.

Another benefit Maven brings over RSS is the ability to handle super bursts of traffic, such as when everyone tries to download the show at once, by limiting the number of simultaneous downloads.

“When there’s a mass audience like with Rush, everyone could go at the same time to get the file, which can wreak havoc on the network when there’s thousands of people requesting at the same time,” says Todd Boes, vice president of product marketing at Maven. Such bursts can result in big bandwidth bills.

Premiere is also trying to make each three-hour show more ‘Net friendly by breaking it up into three separate MP3 files.