Usually, it's hard to get a new computer connector to catch on.
But Apple, which by selling more than 400 million iPhones has plenty of clout, isn't bound by the usual constraints. Thus, you can bet that the Lightning connector that debuts on the new iPhone 5 will be a success.
The cable replaces the 30-pin connector Apple has used since 2003, back when it had only iPods to hook up. Like that connector, it's got a USB connection at one end.
But at the business end, where it plugs into the phone, it's a lot narrower. It's got eight electrical contacts on each side, configured so it doesn't matter which way you plug it in -- a bugaboo with USB cables, particularly as they get smaller. And it's more durable, Apple said.
Even though Apple sells a $29 Lightning port adapter, the new technology will mean obsolescence for some older accessories that relied on the 30-pin connector. "This adapter lets you connect devices with a Lightning connector to many of your 30-pin accessories," Apple said on its store page for the adapter, but then added a big caveat: "Video and iPod Out not supported."
Today's announcement fulfilled reports of a new iPhone 5 connector, though not the rumored 19-pin design.
More unclear is what the future might hold for Lightning. During its press conference today, Apple said Lightning has an "adaptive interface," which implies to me future versions might be able to plug into something besides USB -- sending high-definition video to HDMI, for example, or synchronizing over the high-speed Thunderbolt port that's on today's Macs.
The Lightning port also is used on the newest iPod Touch, also announced today and also sporting the larger four-inch screen that's part of the iPhone 5.
It's hard to imagine your iPhone slotting snugly into an old dock with an adapter in the way, though.
You can always throw more money at the problem, however: Apple is working with accessory makers including Bose; JBL; Bowers and Wilkins; and Bang & Olufsen on support for the new connector.
And the industry will follow. Apple and Intel have a significant challenge getting Thunderbolt to catch on, given that it competes with USB 3 and is a premium technology, but with millions of iPhone 5 models about to hit the market, Lightning is a mass-market reality.
Corrected 2:54 a.m. Sept. 13 to note that the connector has eight contacts on each side.