On intellectual wastelands such as Facebook (and various forums) you see comments like "let 'em go" "They will struggle following independence" etc etc, conveniently through intent or negligence to consider the rest of the UK if this happens. The impact in terms of cost alone to England to basically comply with this will be enormous, hitting funds that Gvmts have so called allocated for key services - the usual ones that get cut when cuts and costs are mentioned. Then there are the cost and impacts to business. Dealing with cross border companies and contracts is currently a minefield and will occur again. I deal a lot with customers in Eire for example and we have to follow a long established set of procedures to comply with the laws of the UK and Eire, establishing and complying with new sets will be costly and beneficial only to those who will charge to make it happen.
Next a comment about "immigration" - As Scotland will be outside of the EU - and probably for some time, there will be adjustments needed for trade and working rights of Scots in the rest of the EU and companies who base themselves north of the border. I know of at least 5 major companies who are looking at moving IT assets into England if they do vote yes - planning for this has to start now - to comply with many of the business agreements and laws. Staffing levels and abilities to trade are one of the drivers behind this.
Also where does this stop, will Wales call for independence, will Cornwall, will Yorkshire, all far fetched (even the Wales thing) but the amounts of efforts dealing with this will be large.