[I love mini-games over loading screens][link], but the reason nobody else does them is [Namco owns a software patent on them][namco] and has since 1998. I wonder if 37 Signals knows or cares?
[link]: http://37signals.com/svn/posts/2234-launch-highrise-for-iphone “37 Signals launches Highrise of iPhone”
[namco]: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=5718632.PN.&OS=PN/5718632&RS=PN/5718632 “United States Patent: 5718632”