I'd be curious to know why Orkney was a given for the "No" vote. I'd have thought the opposite, given the remoteness from England and the deep Nordic roots.
DISCLAIMER: This following is by an outside observer, and may not be entirely accurate. Apologies to people on the scene like Owlbread in advance.
Actually, those are likely contributing factors to their vote; to them, Holyrood is as distant in terms of political and cultural tradition as Westminster, but it's a heck of a lot closer in terms of political power. During my research, it seemed to be that the Gaelic and Scandinavian-influenced regions were considered givens for the No camp in general - specifically, the Highlands, Orkney, the Western Isles, and Shetland. The SNP's roots are more generally in the Scots-speaking regions (that is, the tongue that is alternately termed as a language in the English family or a dialect of British English, as opposed to the general term for people who are Scottish); that 19th-century-romantic vision of "Scottishness" pioneered by people like Walter Scott (whose romanticized, fanciful depiction of Highland culture actually made it popular to emulate in the Lowlands, instead of the usual perception before him as a barbaric nest of backwards Jacobites) has been much of what they've peddled, but in Scottish history, the Lowlands and Highlands have typically more often been in conflict rather than united. As well, the latter three in particular have far closer ties to Scandinavia than the rest of Scotland, and have fairly distinct politics from Scotland; glancing through the last four elections to the Scottish Parliament, the SNP only took one of them by 2007 (Western Isles), and even in the SNP sweep in 2011, Orkney and Shetland remained LibDem. In fact, going back further, Orkney even voted against granting powers of taxation to any devolved parliament in 1997, a result only shared with Dumfries and Galloway on the
English border. I imagine there are two major thoughts on the matter. Politically, the Isles are more likely to be "oppressed" (as unlikely as that would be in either case) by an independent Scotland founded on "Scottish" principles than a federative Great Britain, and there would be more allies to make political common cause with against Westminster (such as the Welsh and other Scots) than against Holyrood (the...ummm...). Economically, oil is as divisive as ever; much of the North Sea oil is British by virtue of Shetland, and certain presumed but untapped oil and natural gas yields (not that I'm saying the "hidden oil" was a conspiracy theory...but it was) are likewise tied to the Western Isles. The oil-driven prosperity of Shetland, largely tied to actual concrete local jobs, is one that would tend to make these people less willing to rock the boat, especially since it's a prosperity they do not owe to Edinburgh and one that the SNP has used and abused as a significant weapon in their political campaigning on the mainland. There was even significant talk of Shetland and Orkney seeking separate arrangement with Crown in the manner of the Isle of Man (that is, as a Crown dependency) should the referendum have gone as feared (moderate Yes as a whole, strong No in the Islands).
I do look forward to seeing if the SNP follows through on the Lerwick Declaration in the event of a defeat in the referendum, and grants the islands their promised autonomy regardless. After all, that was part of the reason why the SNP rejected a referendum on the status of the islands in or out of Scotland. I've not been impressed by them to date, but if they can prove more gracious in defeat than they were when they presumed victory, then my heart might be slightly swayed. Just a little.