welcome to the happy world of DS spongy. i haven't played nintendogs or warioware yet, but i also recommend the games "meteos" and "kirby: canvas curse". i bought "yoshi's touch and go", but my girlfriend plays it too much for me to give a solid recommendation yet.
keep me posted on the nintendogs though... i've considered trading my manly dignity to give it a shot, we'll see i guess.
btw, free wireless internet play is coming in a couple months. anyone down for a TFP mariokart tournament?