Not as far as I am aware, and Christmas Day, lol.
Some quick questions:
Any updates on any missing episodes being found?
When will the X-Mas special air?
To expand a little bit - on the day before and of the 50th some stories were in the British newspapers claiming that more episodes had been found, and that they might be announced that night. They ultimately weren't, but the stories were so clean-cut sounding that perhaps they were found and some people at the BBC blabbed to the papers in 50th excitement.
Depending on what source, it couple be one complete serial or multiples. The most common thing that every source seems to 'agree' on is that all seven episodes of Marco Polo, a missing 1st Doctor story, have been found. Not found in the traditional sense, though - allegedly the media fuss over Enemy of the World and The Web of Fear made an old fan check their collection, and they found a copy of Marco Polo they'd recorded off the TV on original airing by pointing a camera at the TV screen directly. The BBC has the original audio for Marco Polo, so allegedly they're cleaning up the visuals from the fan's recording and attaching the original version of the soundtrack to it.
Some other, more shaky rumours suggest that other stories, such as Power of the Daleks, have also been found but will take time to trickle through.
God, don't remind me. I hated that shitty ending for such a great character.
Is it really shitty? I don't know. Like, she never would have left, like Rose, like Amy - that's the point of her character. The 'stranded' line was played out with Rose already, and Donna's character was such that she never would have left of her own volition. They could've played a different take of the stranded card - this is what they did with Amy - but even that was less convincing, plot-wise, mechanics, wise, than it was with Rose. The only thing I could've seen her leaving for was Wilf or her mother dying, which would've been even more fucking dark.
In the end, the RTD companions all lose that which is most dear to them. Rose chooses the Doctor over her own family - even one with her parents reunited - multiple times. So they take him from her in the most painful way possible. Martha is shown in her very first scene to be the glue that holds her family together, and while she loves travelling with the Doctor, the first thing she thinks about on multiple occasions is her family (42, for instance) - and so her family end up torn to pieces, emotionally and physically scarred as the only few who remember life under The Master. Donna's life was given meaning by all the things she and the Doctor did together, and so memory of all those things was taken away, leaving her as the awful, vapid woman we first meet. RTD's universe is crueller (Amy may have lost her imaginary friend, but she still has the thing she consistently chose and marked as the most important - Rory) but it's also nicely circular with each of them.
There's only so many ways companions can leave, really. They can die - which is really too traumatic for a much-loved regular on a kids show, and I'll be surprised if they ever do an Adric again - they can be forcibly separated from the Doctor, or they can choose to leave. The middle one was the correct one for Donna. Amy had a few potential exit-points, really. She could've left of her own volition twice - at the end of Series 5, having rescued the Doctor and started her life with Rory - and at the end of The God Complex, where he drops them off to "save them." Once she and Rory came back again after that,t hey really reached the point where the only way they could go was forcibly, as they'd back-and-forthed too much on it at that point, it was clear they'd never really let go unless forced to.
The really sad thing is that Catherine Tate turned around after she'd filmed the end of Series 4 and said to RTD/Julie Gardner "I wish I could do more!" and also begged them to find a way to get her into Sarah Jane Adventures, as it was her kids' favourite show. RTD later cursed this, and said he assumed that after a year she wouldn't want to do any more as compared to all the other New Who companions (even Karen who now has all her roots going down in the US) Catherine is by far the most successful on her own terms - massive-rating comedy sketch shows of her own that she writes & produces as well as stars in and so on, plus kids to care for. He said flat-out if he'd known he'd have kept her for the specials year and found a way to write her out in the Tenth Doctor's final episode instead. It was her saying she'd come back that led to the thought process of having Wilf instead of a one-off companion, though.
I rewatched Blink recently and would be pleased if Moffat brought Sally Sparrow back as a companion.
Her comments on the fandom aside, they'd probably never get her back now anyway, I guess. She's got that big old Hollywood career - she hasn't done a single piece of TV since 2007, the year she did Blink, and most of the productions she's doing now are American. She's too big for the show, I reckon. Who does get the odd Hollywood get, but they tend to be older actors who have less to lose by doing smaller TV projects for fun. Like Hurt, in fact! But, eh. Sally had her story and it had a wonderful finite end. She got her life with Larry and it's nice sometimes to let those characters live in the world that was given to them without revisiting them again.
If anyone from that sort of era, it'll end up being Georgia Moffet (or as she's now being credited, Georgia Tennant!), Jenny. Moffat was the one who asked RTD to change that script so that she lives at the end, and I do slightly wonder if plans to use her in his run were scuppered when against his own plans he ended up casting Matt, because he's only three years older than her and that'd be a weird Father/Daughter relationship no matter how old Matt plays it. She would've made a great third pillar with him and River. Anyway, Capaldi is only a few years younger than Georgia's actual father, so if he wants to revisit that he now can.