Thanks to everyone that +1'd my logo.
Here's a bit of an improvement, including what I think would be a good slogan.
Here. I actually took a few minutes to clean it up and do it in Illustrator rather than my quickie earlier version.

Loogs good - I think the tag line should be just 'digital cash' because cash is private and instant already

EDIT: I like that the first letter D looks like reversed C for Cash..Dash! v good
Could have animated version with the D rotating to a C and back..(rotating around Y axis if u know what i mean)
Good point--so what do you think of the slogan "
Dash IS Cash"?

I think just: Digital Cash
Cash is by definition private and a cash payment is settled instantaneously. So in my opinion Digital Cash is more simple, and self explanatory.
Specially at the beginning, later on, when the brand develops we drop digital cash, and leave it just DASH. There is no need to give it explicit meaning it will grow to represent the payment platform, it will just take time.