I'm sorry, but it isn't going to happen. Right now, I'm playing with the idea of developing a simple client that is specifically for Ubuntu and would be distributed through the software center since there are so many developer resources Ubuntu is putting out that's geared towards producing applications that integrate with their OS. If I was going to do it, then it would progress slowly since I'm a student that's working on his double major and is holding a job. (Computer Science and Business/programming teacher for kids 10 and over - for those who are interested)
I like to fantasize over building the client using Vala or C++ and GTK3 but fantasizing is a far stretch from actually going through with it. If I get something together then I'll post it right away for the attention of everyone. Also to note, NixNote is a client that's available for Linux - which would be something you may be interested in. While I highly respect the developer for putting forth the time and effort into building the client, I feel that something built using Java/Qt is just too resource inefficient and is hard to integrate into the Gnome environment while, at the same time, sporting a snazzy look.
tl;dr: I might do it, but don't quote me on anything.