I would say that the HP TouchPad the was "Bang for Buck Tablet of the Year 2011" - no other tablet on sale for under £120 last year came close to it. Being able to dual boot, customise the kernel, overclock and run gazillions of apps made it a steal (far more so than any iPad to date).
However, nearly a year later, things have moved on - Apple finally released a tablet with a decent display (i.e. one significantly better than rivals for the first time) whilst keeping the price at silly money levels and we've seen a slew of Chinese tablets appear at under the £100 price point. However, there's been nothing for ages that isn't a compromise on performance (those Chinese tablets are often underpowered, particularly for the CPU and screen resolutions) or price (the iPad 3 is a nice tablet, but you pay an extreme premium for it).
I didn't want another 10" tablet, I didn't want a 4:3 screen ratio (bad for watching movies) and I wanted to spend less than £200, but still have a good resolution and good CPU/GPU combo, plus it had to be Android of course (the newer version the better - 4.0 at a minimum).
It wasn't until this week that the Nexus 7 tablet fufilled my requirements and I put an order in for one at £179 - using a £20 discount voucher code - at Tesco Direct (5% Quidco, 179 Clubcard points and £15 Google Play credit). I think this tablet is the best bang for buck tablet this year - yes, it has no SD card or HDMI, but neither does my TouchPad, so I don't hold that against it.
It does mean my TouchPad will be gradually relegated in its duties from now on - it'll probably become an XBMC remote control/client as its main use, particularly during the Olympics.