Here in Southern New Hampshire, landslides are uncommon. The last one I can remember is a mudslide that blocked part of Route 101 (a major east-west road) in Wilton in April of last year. This is emphatically not true of other locations, however—the Indian state of Kerala suffers frequent landslides caused by the monsoon rains while parts of California are especially prone to mudslides especially after forest fires as are parts of Indonesia.
Trying to identify those sections of terrain most likely to slide is important and several projects, including the Italian Landslides Inventory (IFFI) project, seek to identify and map slope instabilities to figure out where landslides are most likely to occur. The next step involves creating alarm systems, which is how the Sensor-based Landslide Early Warning System (SLEWS) came into being (click here for a PDF of a longer academic paper describing the system in greater detail). This EU-funded project is part of WINSOC, a targeted research effort aimed at developing wireless sensor networks and adopting biology-inspired techniques to achieve greater reliability and accuracy.
According to the article "Wireless sensors learn from life", published in ICT Results, the project couples a variety of sensors with wireless nodes to monitor the Idduki rainforest of Kerala province. The nodes relay their information to a satellite from whence it heads to a central control. The ad hoc wireless network is combined with Web services for data processing and retrieval.
This is one of the great promises of wireless sensor networks: to be able to quickly and easily deploy a series of sensors in an environment, create a robust network for data acquisition and retrieval, and to enable a much richer picture of happenings in the monitored environment (agricultural monitoring, for instance) and to allow you to do something useful with the data (e.g., helping first responders navigate through a collapsed building, spot landslides early, assess post-earthquake building damage, or alert you to forest fires). As the planet's weather patterns change this kind of rapid response monitoring is going to become more important. It's a good thing that so many very smart people are trying to figure out how to do it and do it well.