The Nexus 7 tablet is the best 7" tablet out there right now!
Fast Quad-Core Processor
Latest Android OS 4.1 Jelly Bean
Great Pricing too $199 for the 8GB or $249 for the 16GB internal storage.
I would go for the 16GB one for only $50 more and 2X's the storage space.
It does not have a microSD card slot for external storage but, you can download the Dropbox app to get more online storage free. There are also other storage options in the Google play store.
I do not own the Nexus 7 but my friend does and he loves it!
I have the Samsung Galaxy Tab 8.9 tablet I bought last year.