Im afraid they may be but I hope not.
Digital only sucks in so many ways.
1.Cant trade or resell
2.People with bandwidth limits and speed will be too handicapped,not all countries or cities,towns etc anywhere have decent speeds or cheap enough plans for larger bandwidth caps.
3. If you delete it off your HDD its gone,you can only download again a few times before you need to buy again (depending on Sony's terms at any time)
4.Prob with your HDD and you lose all data,need to download again,see number 3 above for probs with that.People may say you may have probs with discs but Ive only ever had that once with PS3. And with so people putting in larger aftermarket HDD's I think the issue with that could be more common.
5.So far all 'new' releases Ive seen are always more expensive than buying hard copy,at least with hard copies you can search for cheaper prices at online shops,ebay,amazon etc.
Unless they incorporate something like that in future PS5 where anyone can sell digital on PSN.
Anyway,Im off topic now,see more on this debate here:
http://ps4forum.com/38-ps4-games/3147-could-ps4-ever-go-disc-less.html