I was surfing around on my Samsung Q1 and found an article called The Ten Most Critical Wireless and Mobile Security Vulnerabilities. The list was assembled by MARA, a group of mobile device malware researchers who want to prevent the spread of malicious code. The list includes wireless, mobile device, and VoIP concerns.
WiFi: I know that many people use the default settings of their WiFi router since my mobile devices pick up these access points all the time. While this may be good for surfing on the road, it is also very dangerous for the router owner. Zero configuration is great for the new wireless user, but it can also be a problem for subsequent logins, as pointed out in the article.
Bluetooth: I use Bluetooth on all my devices and personally have not experienced or attempted to try BlueSnarfing, BlueBugging, or BlueJacking and wonder how common a practice they really are. You have to be in pretty close proximity to someone too. I am concerned though with all the new laptops at work including Bluetooth with users not even knowing what Bluetooth is.
Passwords: I think the biggest danger for mobile devices is loss or theft and then not having your data secured. There are 3rd party apps available, but even some of these store the passwords as text in the registry.
Autorun: I was unaware of the autorun feature in Windowe Mobile and will have to take their advice and create a dummy autorun file.
There are some other sections that make for interesting and educational reading. We should follow these minimum guidelines to help keep our devices secure as possible.