SMB (Super Mario Bros) was pack-in wasn't it? Are you talking about NSMB? If so, look here. (http://vgchartz.com/swlaunch.php?reg1=All&game1=New+Super+Mario+Bros+-+DS®2=All&game2=Super+Mario+Galaxy+-+Wii®3=All&game3=&weeks=12&weekly=1)
Now, let's go week to week, ok?
Week one: SMG is launched in Japan, NSMB in NA:
SMG: 260K vs NSMB: 174K.
Week 2: SMG is only Japan, NSMB Japan and NA.
SMG 78 K vs NSMB 1031K
Week 3: Both in Japan and NA
SMG 904K vs NSMB 419K
Week 4:
SMG 604K vs NSMB 373K
Week 5:
385K vs 318K
Week 6: Both launched in Europe
442K vs 281K
Week 7:
557K vs 390K
Week 8: Christmas boost for SMG, no reason to count this, to unfair, anyway:
943K vs 369K
Week 9:
326K vs 303K
Week 11: The typical drop after Christmas for SMG
174K vs 252K
Week 12: Still drop after Christmas:
162K vs 228K
Week 13: Only European Data at the time.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS