What bugs have you found? Have you reported them to Apple?
I haven't found any since the 10.9.1 update. They fixed the quicklook slowness bug which was my only complaint. Mavericks is one of the most polished OS X release I have used, behind Snow Leopard.
(not op) I have 4 reported to Apple about Mavericks and one (Quicktime) was fixed with 10.9.1. The other 3 are on the Finder, first appeared in 10.9, and were not fixed in 10.9.1. Mavericks has the buggiest Finder I have seen on a 10.x release. It is a pain to have to restart Finder multiple times a day.
Move some picture files from one folder to another with preview item on and watch the finder hang after about twenty files. It is damn near unusable at this point. I gave up for big sorting and just have a button on the finder toolbar that opens a terminal in the folder the window is showing and do copies that way.
I have a weird issue where, after upgrading, opening the Activity Monitor causes a process called 'systemstats' to balloon to >1.5GB memory and peg the CPU. Doesn't seem to be just a startup thing, because it does it indefinitely until I kill the process (closing Activity Monitor doesn't fix it). Googling around turns up some other people with that issue but no obvious diagnosis.
I would say at least the Finder in Mavericks is "buggy as hell"[1]. It looks like it has a real issue with preview images (when the file is dragged to another window), Applescript, and updating based on file system changes.
Mavericks is absolutely a regression. My Mac Mini i7 (2013), for instance, will regularly recover from sleep with a black screen. Now if you are careful you can log in (hope the context is in the password box, type your password and return), but this has been there since Mavericks release. Many people have reported it. Still there. It is among a long list of bizarre oddities and system quirks that simply didn't happen pre-Mavericks.
I haven't found any since the 10.9.1 update. They fixed the quicklook slowness bug which was my only complaint. Mavericks is one of the most polished OS X release I have used, behind Snow Leopard.