I dunno, I think those MHP3 shipments are fine. Within a month Capcom will ship more copies of MHP3 than they did total for (full price) MHP2G, and they're expecting to ship another million on top of that by the end of March. That's a HUGE increase for the series already, I think some people's expectations are getting bit unrealistic if they expect better than that.
Previous 1st week MH sales for comparison (via Famitsu)...
- Monster Hunter (PS2) 124.060
- Monster Hunter G (PS2) 128.051
- Monster Hunter Portable (PSP) 118.317
- Monster Hunter 2 ~dos (PS2) 368.057
- Monster Hunter Portable 2nd(PSP) 746.313
- Monster Hunter Portable 2nd G (PSP) 823.265
- Monster Hunter G (Wii) 142.452
- Monster Hunter 3 ~tri (Wii) 582.548
- Monster Hunter Frontier Online (360) 82.490
- MonHun Nikki: Poka Poka Airu Mura (PSP) 280.521
- Monster Hunter Frontier Online Season 9.0 (360) 17.713