From TidBITS (Rich Mogull)
The original iPhone was widely criticized by security professionals for lacking essential security features for the enterprise, the large corporate networks that have special needs because of huge numbers of users and the massive back-end operations to support those users.
The original iPhone was hard to lock down, had only limited secure connectivity options, and lacked both data protection and some way to destroy data remotely if you lost the phone. Those capabilities have continued to improve with every iPhone software release and, combined with the hardware improvements in the iPhone 3GS, even regular users can now enjoy security equivalent to that provided by most corporate environments. Read the full story [tidbits.com]