Some more details have been released from the supposedly "bombshell" Survation poll, and the first thing to say is that this is a genuine 50-50 poll. Not only is the headline result 50-50, but on the raw numbers it's as close as it can be - after weighting, 380 respondents said they would vote Yes and 382 said they would vote No, which works out as Yes 49.9%, No 50.1%. Some people are placing huge significance on the fact that, if Don't Knows are left in, the percentages appear to show No ahead by 1%, but a) that's just a random quirk of the rounding, and b) those aren't the headline results anyway (although for some strange reason they're the ones used on Wikipedia's list of polls). This is a dead heat, and it shouldn't be treated any other way. The somewhat less good news, though, is that the fieldwork was conducted on both Thursday and Friday, which means the impact of Friday's explosive events will not have been fully factored in.
There are also Scottish Parliament voting intention numbers, which remain exceptionally good for the SNP -
Scottish Parliament constituency ballot voting intentions: