There are a lot more issues than just getting used to a new set of tools.
I recently set up a new small startup company. We have 4 staff, but 3 of us work a lot from home, coming into the office only once or twice a week. As an experiment I set us all up on Google Apps Premium. The email is great - no complaints. Gmail has always been my webmail of choice, and with POP/IMAP support my 2 Mac guys can use mail.app to their hearts content.
Calendar is so-so. Sharing calendars, particularly more than one seems a bit erratic, but it's just about good enough for us to use (we really need shared calendars do the the business we operate).
Docs is the main weakness. The office suite just doesn't have the feature set of any of the offline suites. Offline support is lacking. It frustrates me that Google make a huge thing of this being a set of "collaboration" tools and yet leave out (or don't implement) a really simple and obvious feature like folder-level sharing. If you want to share a folder containing sub-folders with other people in your group, you have to meticulously go through the directory structure and share all the bloody files in each sub-folder individually. Why the hell can't I just share the top folder and have it apply sharing to the rest of the tree?
What worries me more, is that when you go into the requested features forum, you can see that people have been asking for this for a long time now and it's not happened. Which makes me think that Google simply aren't putting a lot of resource into developing it. I don't like entrusting the future of my business into something that they might just drop like a stone if they feel like it. And without more feedback from the devs, and noticeable improvements over time, it certainly feels like they could.
The docs file manager tool itself seems completely brain-damaged at times. You can drag a file from one folder to another, and it disappears. The folder displays (2 items) but only 1 is visible. Where the fuck did it go, and why should I have to kill my browser window and re-launch to see it? I could go on, but I think a couple of examples are enough to suggest that there are what I would suggest are basic areas of functionality that simply aren't ready for prime-time yet.
Eventually we gave up and went back to an offline office suite. Google Apps is a nice idea, and I'm sure that when it's anywhere near fully functional it'll be a very handy for us. But right now it's not even close.
I apologize for the rather disorganized rant. If I'd had more time I'd have written a more organized critique, but given that I was on my way to bed, I banged out this comment in a quick 5 minute brain splurge.