This has appened to me too, extremely annoying. It only occurs on my phone, both on 3g and wifi. Killing the app and reopening sometimes works, but sometimes wont reconnect to the game.
Internet disconnects

captinkangroo1 Bad news dept: Your PC is another suspect, not just comcast or chess.com
http://blog.chess.com/NimzoRoy/diagnosing-and-fixing-internet-problems
About 2 to 3 games late at night the connection when I am playing is interupted and the board turns a foggy white. I am always ahead on time (bullet) and when my opponents clock is close to running out the clocks switch and I get tagged with the loss even tough is is their move and their clock winding down. Happens only at night. I get tagged with the loss even though it was their move EVRY TIME. I NeVER get the win and it usually happens after midnight. It has taken me from a 1366 to a 1058 in three days and when I see this I know my rating is going to drop every time. Anyone have an idea what causes this. I know server capacity is switched around the globe to the areas with the heavist activity ie the Far East after 1:00 A. M. CST. Daytime is ok and the speed varies. I'll win a buller blitz and loose the next one when this happens. Sure would like to know if it is chess.com or Comcast. Comments would be appreciated.