I bought Justice League #1 through my iPhone last night at 8pm. Here are the many reasons I found this to be awesome:
1) I didn't have to spend $8+ in gas to get to the nearest shop (which was already closed at that time).
2) I didn't have to wait until the shop was open to get it.
3) I didn't have to spend more money on other stuff that I'm not as interested in to "make up" for the gas money.
4) I don't have to bag it, board it, store it, move it.
5) I could read it on my computer before it downloaded to my iPhone.
6) The creators still get money from it.
7) If I really like a series, I will buy the trade from my comic shop, so both they and the creators will get money from it.
8) I don't have to bag it, board it, store it, move it. Seriously. This is HUGE for me.
I can't WAIT to get an iPad, primarily for this. And this is as someone who has worked in some aspect of comic book retailing off and on (mostly on) for almost 20 years (since Oct 1992). Trades are where the physical direct market is heading - ESPECIALLY now that Borders is out of the picture. In a typical week at the last store I managed, Wednesday (or new comic day on holiday weeks) was the ONLY day that single issue new comics would have a higher total dollar amount sold than trades/HCs. And if a Walking Dead or Fables trade came out that week, sometimes the trades would overtake that too. Trades also do AMAZING things for cashflow with Diamond's reorder system.
Physical single issues are ALREADY print-on-demand. The numbers for a print run are set two to three weeks before the book hits the shelves, and it's a combination of retailer orders, Diamond's willingness to risk storing extra copies for reorder, and the publishers' willingness to share the risk on storing extra copies for reorder. Most of the time, it's better to sell through and get a new printing out 3-4 weeks later - preferably to sell with the next issue. But it's still very rare that the system hits the "magic number" where you have 100% sell-through and everyone that wants a copy has a copy.
Digital ties up zero money. None. And when a book sells, the distributor gets money. The publisher gets money. The creators get money. And the person that buys the book gets to READ THE BOOK. And Comixology has offered to help retailers sell vouchers for digital comics through their stores - which is a complete no-brainer in my mind. Why would you not take your 20% cut of a product that you didn't have to put out ANY money for and don't have to maintain or store AT ALL? Sure, you may get 40, 50 or 60% out of a physical sale, but then you have to factor in freight, handling, storage, and the chance that the book won't sell.
Nostalgia is fine and all, but print is just not a worthwhile business model anymore.