Basically, that analogy is true. The X360 has had a ton of great sellers in the US, and for the most part, the saying "good games sell good" is true.
Consider gamerankings top-20 list for the X360:
#1 - Oblivion (1.2m US units sold w/o a GOTY edition)
#2 - Gears of War (2.8m US units sold + 10k/wk still)
#3 - Guitar Hero 2 (1.0m US units sold + 25k/wk)
#4 - Ghost Recon AW1 (1.3m US units sold)
#5 - Castlevainia: SOTN (One of XBLA's highest-bought games)
#6 - Call of Duty 2 (1.3m US units sold)
#7 - Forza Motorsports 2 (450k US units sold + 12k/wk, 1m seller now/soon)
#8 - Rainbow Six Vegas (1m US units sold + 8k/wk)
#9 - Burnout Revenge (340k US units + Bundle Sales + Worldwide are around 750k for a spin-off from actual Burnout games)
#10 - PGR3 (500k US + Bundles + w/w are just under 1m)
#11 - Shivering Isles (45,000 downloads tracked just via MGC, most likely near 10% of all Oblivion owners have SI installed @ $30/ea)
#12 - Geometry Wars (most-downloaded XBLA game)
#13 - Ghost Recon: AW2 (600k US + worldwide cume is near 1m, or more)
#14 - Dead or Alive 4 (400k US/Japan cume + worldwide, good numbers for a fighter)
#15 - Fight Night Round 3 (1m in US alone)
#16 - Dead Rising (750k in US and counting, 1.3m w/w)
#17 - NBA 2k7 (550k in US + WW cume)
#18 - Viva Pinata (about 275k US/Japan)
#19 - Splinter Cell: DA (600k US)
#20 - FEAR (400k US cume).
So from the top 20, only 4 games failed to reach 500k in the US - Fear, DOA, Burnout and Viva. 10 are either million sellers, or very very close worldwide. I say that X360 gamers are rather smart, as very few games on the top 20 have sold 1m copies, and only VP really failed to do very well, and even then, is still charting in Japan, and is recieving a new title this year.
This is why attach ratios are the way they are. The games that rank good, do great.
Back from the dead, I'm afraid.
