According to
IGN, E3 no-shows,
Valve will be in Cologne, Germany for Gamescom. What does this mean? It could be that we will finally get some information on Half-Life 3 (or HL2: episode 3), but more likely any announcements they make will be for games we already know about, like Portal 2 or DOTA 2; however, a gamer can dream, can't he?