The thing a lot of people dont understand about android is that the apps you download are free to do whatever they what to your phone like send your info to their servers, make calls or send text messages from your device without you knowing. iPhones don't have this security issue.
I can see the android market getting a lot of fake apps that look like they are for one thing yet they do something completely different like monitor/collect information (spyware) or can be used remotely by the creator to do things like issue DOS attacks on servers.
Just think, some programmer (probably a 13 year old) could put out a fake app the a bunch of people like and download. Then use that to control thousands of cellphones instructing them to attack and bring down a major website.
could even see some sort of terrorist attack this way and bring down all the cellphones. People go crazy when there is no cellphone service and are also unable to call 911.