I have been very impressed with GMail. Especially now that they will let you host your own domain. However, IMAP is still too important for me to give up for my main business account. Let me explain why.
There are three main ways to read your email. Webmail is one. The other two are called POP3 and IMAP. POP3 is what Google uses. It allows you to download your emails to your local computer. The problem is that it doesn’t keep things synchronized or allow folders. So if I move an email to a “to-do” folder on my client, the server doesn’t know anything about it.
If I just used one computer that wouldn’t be a problem. However, I have three computers that I use on a fairly regular basis and I need to be able to get to email on all of them. IMAP allows me to do this. If I make a change on one computer it automatically updates it on the other computers. If I create a new folder, it automatically creates it on the server which is automatically synced with my other computers and it shows up in web mail as well.
By using the IMAP protocol I’m able to have the same view of my inbox regardless of what computer I’m using. Of course if you use Gmail over the web, it gives you this capability as well. Internet coverage isn’t ubiquitous enough for me to take this route yet. However, it might be some day. Until then I’ll stick with mailboxes that allow me to use IMAP for my main business accounts.
The other day I was trying to help a fellow blogger get his email set back up after his computer had crashed. Since he used POP3, he had lost all of the emails he had previously downloaded and he had to send out messages asking people to resend anything they might have sent to him.
With IMAP this is not a problem because the server keeps a synchronized copy of everything that is on your desktop computer. This is a very valuable feature–especially if losing an email could be costly.