Forget about iPhone! Think Windows Mobile 6.0 if you are business user using Exchange 2007 as mail server.
If your current activesync setup is on the exchange version 2003, windows mobile 6.0 will still support. Nevertheless, the currently implemented activesync in exchange 2003 will not take advantage of all the new features introduced in windows mobile 6.0.
In a nutshell, the following self explanatory chart will help to explain the key difference between Windows Mobile 6.0 & Windows Mobile 5.0
If you look at the below picture of Windows Mobile 6.0 Device, it is clear that iPhone is not the only new kid on the block giving a trendy great new-look with sensitive touch screen interface. Here is a great demo on youtube
The iPhone is lacking core business features such as Wireless Email using “Push Mail” technology. The below picture shows Microsoft Exchange support, but it looks to me potentially is IMAP support. My first reason to guess this way is due to lack of official announcement from Apple regarding Exchange ActiveSync availability in iPhone. This could be one of the main reasons why corporates sent out mail to its employees worldwide advising not to buy iPhone, because employees might be in an impression that they can hook this iPhone into their corporate mobile messaging system (e.g., BlackBerry, Exchange ActiveSync OR Good)
Enterprises needs Microsoft Exchange ActiveSync, Blackberry connect or Good Technology compatibility for its employees to use the phone on the road to check email, calendar & contacts.
I guess Apple will introduce business support on its next model or through some kind of software upgrade/update. As of now, Windows Mobile Device works better for me as “smart phone” usage.
After all the noise and drama in launching iPhone, I still cannot understand why iPhone storage is limited to 8GB. It should have come up with at least 16GB.I wish we had a Zune Phone, converged from Windows Mobile 6 & Zune I suggest you read this tips before buying iPhone.
People are complaining for not having 3G in iPhone. I think, Apple chose EDGE rather 3G due to more coverage world wide. Again, it will not be a big deal for Apple to come up 3G, hopefully Apple might consider this in its next model. According to Microsoft, Exchange ActiveSync Licensing is extending to interested parties, read the quote below and more here.
“Microsoft offers a commercially reasonable, nonexclusive license so that other companies can use the Exchange ActiveSync Protocol in their own products. Microsoft will license its trade secrets and necessary patent claims for implementation of the protocol specification.
Microsoft offers a license for this mobile device synchronization protocol for Exchange Server 2003 and 2007 with documentation. The Exchange ActiveSync Protocol license is for a five-year term and based on annual projected sales volumes. Standard pricing is $100K or first-year’s royalties, whichever is higher, with a per unit royalty thereafter. Other pricing options are negotiable when appropriate.”
I suggest you read 
