Your initial reaction(s) may be that Mailplane is nothing more than a dedicated "browser" to access Gmail. In its simplest form, that is exactly what it is. The real beauty and usefulness of the application happens behind the scenes.Mailplane, Gmail will replace your desktop email client
Truly, what is the big deal here? Do I really need Growl notifications of when I receive new mail in my Gmail account? Merlin Mann suggests we should check our mail check our mail LESS often, not MORE often. I watched the demo and didn't see the big deal with being able to drag and drop files instead of having to click Browse and select a file the old fashioned web browser upload way.
The greatest criticism I have is the lack of support for HTML signatures. I am forced to use Firefox/Flock because of the Better Gmail plugin. If I can't have my fancy signature than this ship is sunk!
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