Some technologies appear to be solid, but never seem to make significant inroads. Others also appear to be useful – and back it up with a steady stream of announcements.

Femtocells seem to be in the latter category. Ars Technica reports that Verizon Wireless will launch a femotocell service on January 25. It links to an Engadget story with a picture of what the femto will look like and a bit of information on the launch plans. The Ars Technica piece says AT&T is discussing with customers the commercial launch of a service that to date has been used by employees. Sprint Nextel already offers a service.

The move already is generating controversy. GigaOm’s Om Malik suggests that the project may be less than beneficial (actually, the headline of his post asks if it is a “ripoff”). The reason is that the femto costs $250 and the service may carry monthly charges. Customers have to provide the broadband connection. Any additional service charges, he contends, are unfair because subscribers already are paying for phone services. Unstrung’s exhaustive look at the femtocell vendor landscape makes it clear how vibrant an industry sector this is. It starts with a good definition of femtos – basically, they are low-power access points that connect devices to mobile networks using licensed spectrum and subscribers’ DSL or cable modems. The report looks at the current state of the industry and a survey of vendors in the femtocell chip, access point and gateway areas. The story features many links and two charts that, among other things, reveal that at least 17 vendors touch at least a part of the overall sector.

The next step for femtos -- and their cousins, picocells -- is to make a mark in the business market. This Engineer Live piece, though written for an English audience, tackles that topic in a way that is relevant in the U.S. Perhaps the most valuable element of the article is providing a clear distinction between the two. Femtos and picos, the writer says, use much of the same core technology. Picocells are more business oriented because they can support more users simultaneously, can link to form a network and can more easily integrate with other elements of an IT environment. Femtos are dumber – but cheaper and, since they are self-deploying, are better candidates for mass commercialization. Cable360 makes many of the same points, and adds another, albeit related, difference: Femtocells are consumer installed.

This interesting piece wades into the tall grass to deal with the issue of the differences between femtocells and picocells. The line between the two is growing somewhat porous. The writer says picocells must be deployed and managed by professionals and thus have higher costs. The goal – especially as vendors turn attention to the SMB and eventually the enterprise market – is to create “self-configuring” picocells. The battle will be between them and next-generation “super femtos” that will combine the advantages of picocells and today’s femtocells.

Femtocells and picocells also have a role in the rollouts of 4G WiMax and Long Term Evolution networks. The technology clearly is progressing, and more announcements are certain to be made in the coming months.