Ok let's talk about that.
I really like three elements in this logo : the planet, both as background and principal element, and the envelope. But I think something could be done on the paper sheet (document). Some more perspective ? I think it's actually a bit flat comparing to the other elements.
Color scheme is good too (blue is a fav color for a lot of people).
and as final point it's good to see some really great work made with alternative tools like Inkscape