Ron K. Jeffries gives his thoughts about Gmail and cites a PC Magazine review of web-based mail services that disses Gmail and a response here.
I agree with Ron. I love GMail too. The 'search and tag' metaphors are so much more my style than 'folders and drag n drop'. But there is another simple thing that makes Gmail win hands down (for me):
When I log into Yahoo Mail I see my folder list, top news stories, a big f a t animated ad on the right hand side, and a few other ads on the left, under my folder list. My actual inbox is another click away . When I log into Gmail, I get... wait for it... my inbox. No ads, no flashing, blinking things.. just my email.
The simplicity of the interface doesn't insult me. It's relatively speedy, clearly readable, and the colours are muted and unobtrusive. It's kind of like comparing Visual Studio to Vi. I'm in the Vi camp.
And I find Google's Reader and Calendar the same. I like the lack of shiny faux-3D bars and stripes. They're functional interfaces, with minimal, unobtrusive advertising. If I were Yahoo or MS, I'd seriously review what it is they're aiming for.
I've demonstrated GMail to probably a dozen people in the last year or so. Three of those were already on Yahoo Mail at the time. Those three are now avid Gmailers. Once you get past the fact that it doesn't work like Outlook, you begin to realize that just might be a good thing.
On a more general, application-wide note, I think keyboard shortcuts are seriously underrated. People somehow take keyboard controls as an indication of antiquated, simplistic and somehow limited application behaviour. But I find myself frustrated when I can't easily find a keyboard shortcut for an often-used command.
Down with Feature-bloat, Up with Functionality!