So, did you kill the Rachni Queen in the original Mass Effect game?
Mass Effect has always been a game where decisions have consequneces. That's a key element of the game right? In the original Mass Effect game, the first true 'boss' character was the Rachni Queen. Once you and your pals had defeated her, you had to make a choice - kill her and thus the entire Arachni Race or let her live.
Those who got the Play Station version of the ME2 were also asked to make the same choice by way of a very cool comic before they started the game proper. In the actual game, and only if you let the Queen live, a message was delivered to you when you first landed on the Asari homeworld (I think from memory!) that the Queen had not forgotten this kind act.
This suggested your decision to save (or not save) would have consequences but nothing come of it in the end.
In a recent interview by Darren Franich with ME3's lead writer Mac Walters some comment was made on that decision and the effect it may have in Mass Effect 3:
Darren "I saved the Rachni in the first game, and there was a little tease about them in Mass Effect 2. How big of a repercussion do choices like that have in this game? Does that mean I get a mission that someone who killed the Rachni wouldn’t get?"
Mac "The thing I will say about Mass Effect 3 is that the choices you’ve made previously, and the differences that those choices represent, are much bigger than they’ve been in the past. There are certain missions that are simply not available at all because of something you’ve done in the past. Those are usually on a smaller scale. It’s a role-playing part. Is Conrad Verner alive or dead? [The presence of the Rachni] has huge consequences in Mass Effect 3. Even just in the final battle with the Reapers. "
There you have it, you probably should have saved the Queen.... unless it's one big long fake out and they sided with the Reapers years ago......