I saw the digital version, too. As a subscriber to the print edition, I don't know if I get the digital version as well, but I highly doubt it.
As such, I went and signed up for a subscription to the digital version also. With the Kindle Fire, it's $0.99 per month; otherwise it's $7.99 for a single issue.
As for what comes out first, I think they are "released" at the same time. But with the digital version, you can access it that day. With the print version, you have to wait for shipping, the post office, sometimes weekends get in the way, etc.. So, ultimately, you'll see the digital version before the print version. I hope this makes sense.
As for the digital version, you get two viewing modes:
*Page View - it looks like the printed magazine page. Print is extremely small - you can enlarge it, but then moving around the page becomes awkward. BUT, you get to see the pictures and layout just like the mag.
*Text View - looks like an ebook; print is definitely easier to read, BUT you get way fewer images and it doesn't feel like the magazine at all.
For me, I prefer the magazine more. Aesthetically, I find it has more eye-appeal. Physically, I'm not as afraid to take it wherever I go and I wouldn't mind if it looks a little rumpled. Flipping back and forth between articles is easier, too.