As i said in another thread i think they should select more people this time to be able to grant the 55.000 visas, more than 100.000 like the other years for the following reasons:
1) Many people will keep thinking that it still works like it did before (through letters), especially people that knows how to apply because all the times they applied before, but they don't understand english, and they will just close the window and don't keep the number, or just don't check it assuming they will get a letter.
2)I'm sure some people will lose the number and they won't be able to retreive it
3)Many people are not really interested in winning the lottery, they just apply to "see what happens" and since they won't get anything at their home reminding them about it, they will just forget and never check again. Just people really interested about moving to the US will remind to go to the site and check their status.