The game sold ~1.23M in just one day... in the UK. http://www.mcvuk.com/news/36482/Modern-Warfare-2-smashes-day-one-sales-record Sales should be pretty crazy.
Maybe its just because I haven't played this series before, but man I suck online. I guess that's what happens when you are going against people who have much more time than I do to play this game. I'm lucky if I get 30-45 minutes in of PS3 a day.
Thats the level that I couldnt get through on Veteran...so I knocked it down a couple notches to normal. Those guys on the roof near the end were brutal. On a side note...I just played spec ops tonight...WOW!! Thats like another game...which totally makes up for a short (although, amazing) SP campaign mode. Had a blast there with a buddy of mine and we only played 4 of the missions. Thatll last us a good amount of time until we beat them all on veteran.
Depends on what level difficulty you are playing. After that initial training level, you have completed 4 levels with 13 more to go (Wolverines included). So, you are about 1/4 of the way done in 2 hours. On normal difficulty, it takes, on average, probably 6 hours to complete.