Barnes & Noble updated their UK website this morning, and it now shows a radically lower price for B&N's 7" and 9" tablets. The Nook HD is now selling for £99, or £30 off the regular retail, and the Nook HD+ is selling for £149. The sale prices are likely also available via B&N's retail partners, so I would check your local retailer.
The Nook HD is a 7" tablet with a 1440x900 resolution screen (the highest of any 7" tablets). It's running a proprietary version of Android on a 1.3 GHz dual-core CPU, and it ships with 8GB or more of Flash storage. The Nook HD+ is a 9" tablet with a 1920x1280 resolution screen. It too is running B&N's own proprietary version of Android on a 1.5 GHz dual-core CPU, and it ships with 16GB or more of Flash storage.
Those prices aren't nearly as good of a deal as the US prices (but they're still decent). The UK clearance prices convert to prices of $151 and $226, and once you factor out the taxes the price of the Nook HD is actually lower than the US price. But the Nook HD+ price in the UK is disappointingly higher than the US price ($149), leading me to wonder whether B&N had only imported a limited number of that tablet into the UK.
On a related note, B&N is also selling the Nook Touch and Nook Glow in the UK at prices so low that I think they are on clearance. The Nook Touch is selling for £29, and has been for some time now. The Nook Glow is selling for £69. That's a lower price than B&N is asking in the US, where the Nook Touch and Nook Glow are still selling at regular retail.
These clearance sales were launched as part of B&N's response to their generally marginal success in the ebook and tablet markets over the past year. Barnes & Noble announced last week that they were getting out of tablets and handing that off to a hardware partner. But B&N will still be developing new ereaders, or so their press release said.