I can imagine the possibility of transferring trojans and other malware by touching somebody. This could create a new age of hacking someone's computers, phones and whatever electronics.
@Dimar:
One would hope they would be smart about it and keep everything received in a pseudo-quarantine until the user approved it, beyond the normal virus scanner/protection we have right now there isn't much that can be done about insecure users though.
Of course not. Think of the technology as a simple cable that connects two devices. The devices themselves are responsible for what they can do and not.