Oh God. Oh God, ohgodohgodohgodohgodohgodnonononononononono...
They did not just do that. Oh, God.
Edit:
Alright, here's the deal. I am still sobbing. Ianto is and always has been my favourite character. And I am in complete and utter denial about this. Gareth is listed as being in the next episode on IMDB, so as far as I'm concerned, he's coming back somehow. He has to because I said so. Call it denial if you want, but I am much happier in my denial than I was before I realized I was in possibly-possibly-not-denial, so this is where I'm staying until I am proven wrong beyond any reasonable or not-so-reasonable doubt.
Also, I totally hope RTD realizes that no one is going to watch this show if it's just Jack and Gwen left. Yeah.
Russell T Davies, I fucking hate you!!!
...
Totally in denial.
I eventually found it:
http://www.sidereel.com/Torchwood/_watchlinkviewer/2474