I've been getting booted from games a lot recently. Its not a force close(still get those somethins) the game just closes and sends me to my home page.
Use a g1
HOW DO U LIVE YOUR LIFE?
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Happens to me on my Google Ion (MyTouch 3G) too. I'd venture a guess that it is a memory leak somewhere and eventually the system just kills it due to lack of memory. Maybe I'll hook up my phone while playing and watch for stuff to go haywire one of these days.