I've cancelled my pre-order for the Fire HD since I discovered that it comes with built-in adverts (apparently, US buyers have the option to pay $15 to turn off the ads., but not UK buyers).
The Blackberry Playbook is incredible value at £130 for the 64GB version. If you Google for reviews, make sure that they are for the current version which is a vast improvement on the original.
More expensive, but much more versatile than either of those, though, is the Google Nexus.