That's about it. I believe they're now trying to find a permanent replacement rather than having guests. Keep an eye on the front page of http://www.ukgameshows.com for any developments.
I too miss Countdown. I did e-mail channel 4 suggesting Tom O'Connor as a possible replacement, but as everyone is saying 'how do you replace Richard?' I hope they don't have 'guest' presenters like 'Have I got news for you'