Absolutely love my iPad Air. Best app ecosystem, great performance. For media consumption (especially streaming) it's unmatched. However I understand if people don't want to pay as much. I have a Nexus 7 as well. It's a good tablet for the price. Great screen too. Just feels like a giant phone. I have also had a Kindle Fire in the past. However that was the first gen. If all you're going to do is surf and read and don't want to spend very much, Kindle Fire or Nexus 7 would be your best bets.
Nexus 7 has been extremely good to me. Only use iPad mini for a couple games and apps at this point - everything else is better on the Nexus. Especially videos: IPad aspect ratio means that widescreen video gets shrunk down to fit. If I'm considering anything new, it's the ThinkPad 10.
Yeah. The Nexus 7's great. I bought it for Ballstreams+Chromecast, but the Ballstreams app won't be updated for Chromecast until this summer. In the meantime, I've discovered I can watch Ballstreams on my Wii U, so the Nexus 7 no longer fills that need. Personally, I've found I don't need a tablet. At all. When I'm trying to get something done, I'd much rather be on my MacBook Pro, and if I can't bring it somewhere, I'd much rather be on my iPhone. However, if I were to buy a new tablet today, it'd be either the iPad Air or Nexus 7.