After some consideration I think I'll keep my Nexus 7 2013 and won't upgrade to the 9.
Reasons:
- Too expensive for just a few hardware upgrades. Still 2GB RAM, not a fan of Nvidia chips, don't care for 2K display (1080P on my 7 is perfectly fine), don't care for camera upgrade on a tablet, etc.
- The Nexus 7 will receive Lollipop this month and it will be like a fresh new start.
- 8.9 might be too big after getting used to the 7 form factor.
- I love the 4:3 aspect ratio, but I watch a lot of TV shows and YouTube videos on a tablet, so the 16:9 aspect ratio of the 7 is better.
Biggest reason is still price. If it had been 299 (take out the 2K display, for example) I would have probably made the upgrade.