So, I've been considering telling my broker to invest in certain game developers before E3, assuming the stocks will go up because of the hype behind new hardware and software annoucnements, but I can't really trust myself to make that decision yet so I'm looking for advice...   

In looking for previous examples of stock going up from E3 hype, I found that NTDOY (Nintendo's stock listing) had an 8 point gain the two weeks after Nintendo announced Wii Fit in 2007.  I'd like to have other examples before I make any decisions though... is there any other evidence to support that investing before E3 is a smart move? 

Also, Nintendo is one thing, but are Microsoft and Sony each spread them selves accross many different markets besides gaming... is it unreasonable to expect their stock to be affected by the announcements of their games and entertainment divisions alone?

What do you guys think?  All opinions are welcome, but if anyone has examples with proven market gains or losses, that would be especially helpful.

Without any inside knowledge this is more a matter of luck than of anything else. Who will publish what and how will this be seen by investors?

Gamers can become excited while investors don't care and vise versa.

Yep, who knows? Sony might bomb their E3, and Microsoft may actually come out with a minority report motion control thing, or the converse.