I've upgraded my home iMac, the WC MacMini, and my work MacBook Pro now to Mavericks and I would recommend the upgrade.
A few minor issues with Safari and Mail Plug-in's not yet being Mavericks compatible but other than that all is working fine. A few points why I like it;
- So far it has been fully stable and FAST! Hate the term but imho it is 'snappier' than ML.
- I like the cleaner interface (e.g. no more silly stitched leather things on iCal)
- Finder improvements (Tabs)
- Better multi-display support
- Truly improved battery life on the MBP
- I want to stay up to date with the latest technology and it is a FREE upgrade
A bit early to tell, but my impression is that with Mavericks Apple is focusing again on better technology and less on 'trendy looks'.
If you are the cautious type you may want to wait for 10.9.1. I've heard about some Mail.app issues but haven't been impacted myself.
Jos