I think you'll enjoy it! People always say, "Macs aren't good for business." When they really should be saying, "Macs aren't good for giant businesses that have already entrenched themselves in a certain way of doing things that it will take years and millions of dollars to dig themselves out of."
Macs are GREAT for small businesses that value communication and rapid change more than they value consistency (aka, stagnation
).
I'm a part owner of a small company, like yourself (just 4 of us), we design and install solar power systems for homes and businesses, and I use my Macbook all the time. Our email is IMAP, I use MS Office to move spreadsheets around (and never have compatibility problems with Office on the PCs in the group). Most of our stuff is webapps (Basecamp for project management, and some in-house webapps for bidding and system simulation) which works great for Macs and PCs.
I recommend reading some of the 'get started' tutorials mentioned, and the "missing manual" series are really well done.
Don't neglect the utility of the built-in iSight. I work in another part of the country than the other part of my company, and before we had iSights, we only used the phone. Its not like we couldn't teleconference with our old computers, we had USB webcams, but with the camera built into the screen, it is so trivially easy that we do it all the time. It was just a little too much of a hassle before, and it is now in the threshold of 'very easy' so we do it a LOT. Saves a ton on cell bills, and we communicate better because I can see the person I'm talking to. I use iChat with other mac users, and Skype with the remaining PC users. I was surprised at how handy it was. With sales reps around the country, you might find this a very useful feature.
So anyway, I think you'll really enjoy it. They are fun computers to use, and for some reason, I'm far more productive with my Macbook than I was with my previous clunky PC laptop (which was getting on in age, I admit). Just be creative, be willing to try out a 'new way' for a little while, and I think you'll find yourself realizing that lots of things that feel weird at first, are actually much nicer once you've gotten through the learning curve.
Good luck with your business!
Peace,
Sam