The BBC and media have a strong interest in telling people that the opinion polls don't tell us anything, as it allows them to impose hype without inconveniences like reality getting in the way
Essentially the question now psephologically is this: is there a systematic error in the polls? There are a few theoretical sources for such an error:
- Dropouts. Essentially, people on the margins of society, who don't have internet access or a landline or are doing irregular work, are harder to reach. If these people all swing heavily in one way (say Yes, as an anti-establishment vote) and can actually be got to the polls they could hoodwink the pollsters as an invisible group.
- "Shy Noes/Enthused Yesses" it may be that people who feel they're in a historic movement are more likely to agree to answer a phonecall from a pollster. This is reduced in election polling by weighting to past GE vote, but that won't work so well in a referendum. This is more likely to boost No than Yes, as the latter has been displayed as having more momentum.
- Don't Knows & late swing. The referendum is still just close enough that the "Don't Know" bloc could swing it. If all these go one way or the other it
will swing the result. But as to which way they might swing we can't tell, and it would take them having a very different uniform swing to the rest of the voters for it to make a huge difference.
All in all, you'd have to bet with the polls, No should win by a narrow margin given the consistency of the results.
On to the non-psephological bits.
Glaurung is very right on the EU and Currency, the SNP seem to have assumed that the world will work exactly as they think it ought to. There is simply no incentive for a UK government to be civil post-independence as there will be no Scots UK voters for them to appeal to. Scotland should expect a very rough ride from the UK on currency, probably the UK wouldn't agree to it short of (ironically) being able to impose budget controls on Holyrood. As for the EU, Spain has a massive incentive to veto entry even if the UK could be persuaded. And they'd certainly not be able to get other things they want out of it, such as an exemption to the Uni funding rules (further irony, an independent Scotland might be cheaper for English students than it currently is).
I just suspect that when and if the world starts calling Salmond's bluffs after a Yes win it will harden both the SNP and anti-independence camps into a "the world is out to get us" and a "we told you so" lobby, creating really quite nasty divides in Scots society, as well as souring relations with England very badly indeed for the foreseeable future. A lot of the SNP reassurances are simply thin air, and I worry about how many Scots seem prepared to assume it'll all be OK when it happens.
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