Want to see the current and future state of ISPs? Check out ISP Planet's quarterly list of the 20 largest consumer ISPs. The shift from dial-up to broadband could mean both good and bad news for consumers.

First, a look at the numbers
The two biggest ISPs are no surprise: America Online and Microsoft Network account for nearly 34 million U.S. residential Netizens. AOL is still the 800-pound gorilla with 25.3 million users--almost three times the number of MSN users. But both companies' numbers are dropping: AOL lost 1.2 million customers over the past year; MSN has 400,000 fewer customers than it did a year ago.

Where are all these people going? Some subscribe to one of third-place United Online's el-cheapo dial-up ISPs: NetZero, Juno, and Bluelight. About half of United's 5.2 million subscribers pay $10 to $15 a month; the rest are left over from its legacy as a "free ISP." Still, United has been profitable for four consecutive quarters--a claim neither AOL, MSN, nor EarthLink (fourth on the list) can match.

But look who's at number five: Comcast, a Philadelphia-based cable company with 4.4 million subscribers. Comcast and 14 of the next 15 companies listed are broadband ISPs. Goldman, Sachs, & Co. projects that by year-end, an estimated 40 percent of the U.S. population will log on from home via cable, DSL, or satellite.

Broadband implications
The shift to broadband means more than just faster surfing. It also changes the power structure of the industry, and (of course) hits us all in our pocketbooks.

Their pipes, their rules. Regional Bells and cable companies dominate high-speed Internet service, and most have a monopoly on broadband in their area. So instead of choosing from thousands of dial-up providers, you'll pick from, at best, a handful of corporate conglomerates. You'll also be at their mercy when it comes to tech support, service outages, and the inevitable rate hikes.

Heftier bills. Forget paying $20 a month for access and content; think $35 to $40 a month for a slightly faster 256Kbps or 384Kbps connection, or $50 or $60 for a high-speed hookup (1.5Mbps to 3Mbps). Exclusive content will probably cost more--if AOL's and MSN's plans are any indication. AOL 9.0 will serve up entertainment videos and magazine content for $15 a month. MSN's upcoming Premium service will offer online financial services, photo developing, encyclopedias, and contact management for an additional $10. My take? Extra cost for extra speed is a fair trade, but more content is less compelling.

Don't toss your modem. One problem with broadband is that it's not portable. Outside of your provider's region, you'll need another way to log on. Your options: find a Wi-Fi hot spot or get a low-cost dial-up ISP as a backup. That's one reason cheap ISPs will continue to survive while pricier dial-up companies become dinosaurs.

Bargaining chips. Here's some good news--for now: the big dial-up ISPs will do almost anything to keep from losing more customers, which gives you bargaining power. Call up your provider and say you're quitting. Betcha they'll offer two months' free access--a nice bonus for keeping the faith.