Limor (and the company she built) has been producing microcontroller and Arduino kits & boards like this for a long time. Digispark reflects a lot of her original work. This is a good thing!
I own two digisparks, and I think the main improvements are the 3.3V/5V and mounting holes. I'm still glad to see more devices filling this niche.
I designed a very similar board. It's currently on order from OSH park. I'll see how it turns out.
www.digistump.com