My point is that new characters aren't spoilers anymore. I don't care who the actor is, just that it's not character and therefore plot information.

I'm not sure a "different character" exception works.

To be more concrete, let's say Gareth David-Lloyd does a guest spot on a new season of Torchwood. (For the record, I have no reason to believe that's going to happen. But anyway.) It would be too easy to conclude that Ianto is back somehow (do we really believe death has to be permanent in the Torchwood-verse?), or he's playing a twin/brother/cousin of Ianto, or his character gets mistaken for Ianto. Any one of those possibilities would be a big plot point.

Well, the last could be done as a throwaway shout-out to past seasons. But still....

It would be too easy to conclude that Ianto is back somehow

If GDL comes back to play Ianto, it's a spoiler, don't post it. If GDL comes back and isn't playing Ianto, it's not a spoiler, post it if you want. Checking that out is *your* responsibility. If you aren't sure if it's new character or not, don't err on the side of spoiling people.

According to what I think I've proposed. If that's not clear, I will try and clarify.

If GDL comes back and isn't playing Ianto, it's not a spoiler, post it if you want.

Except that if it's posted in black font, it means he's not Ianto, which may not spoil exactly who he is playing but does say something that could be considered spoilery. Sort of. If I squint.

Seems to me that an actor returning to a show s/he has previously appeared on would be considered spoilery, regardless of the character s/he would be playing. But it also seems fairly unlikely for a returning actor to *not* be playing the character s/he was playing before.

I've seen it twice, but, yes, fairly unlikely. And I would guess that especially in sci-fi shows, even if the promotional material states that the returning actor is definitely not, certainly not playing the same character, there is room for a ~*twist*~. But it would be a twist for everyone, so I guess it wouldn't count as a spoiler to parrot the party line.

it also seems fairly unlikely for a returning actor to *not* be playing the character s/he was playing before.

Unless the show is filmed in Vancouver. Or is Law and Order, where people appeared across the franchise or showed up as someone new all the time. Similarly, to a lesser extent, the CSI family.

Except that if it's posted in black font, it means he's not Ianto, which may not spoil exactly who he is playing but does say something that could be considered spoilery.

Yup. I accept that. I don't think it's spoilery enough or prevalent enough to prevent me proposing said change, but I get that people will vote against it for that reason. It's all good.

There are very few occasions where someone famous enough to warrant a post is playing two different roles on a show.

There are very few occasions where someone famous enough to warrant a post is playing two different roles on a show

Famous, or niche? Because I am all about the niche. Is is accurate to say I've tracked more than one actor across multiple identities on CSIs, and CSI sucks. If someone else were to ever give me a heads up, I'd be grateful.

There are very few occasions where someone famous enough to warrant a post is playing two different roles on a show.

Cecily/Halfrek?

[edit, nevermind I completely misread your post.]