I think the like<>hate powershell arguments are coming from two different camps. The lovers of powershell are coming from very large companies where many hundreds or thousands of mailboxes are being managed. The vast majority of GUI users are from smaller companies where IT personnel must wear many hats and not just e-mail hats.
I work at a company with just 125 employess across 5 sites, but I am the only engineer. I have a database guy I work with, but he has the luxury of only having to manage his ONE software package.
I see value in powershell, but due to my very heavy workload I just don't have the time to learn the many many powershell commands. I loved Exchange 2003 System Manager a lot more than the Exchange 2007 Management Console. So many of the small things I need to do I can find in the GUI relatively quickly whereas I need to resort to technet to find the right powershell command.
Microsoft needs to remeber a that a VERY good GUI is required for people like me. I am just as likely to jump to something else that is easier to manage if the situation does not improve on the GUI side. That is where Microsoft made it's bread and butter.
Many other products web based admin tools are better than the Exchange Management Console. It was almost as if the GUI was an afterthought.
Microsoft needs a consistent develpment path that does not reinvent the wheel with each new version iteration. Don't forget us smaller guys who are too big for SBS and too small for dedicated e-mail techs learning Exchange the powershell way.