OS X Mavericks Upgrade: Wait or Download Straight Away?
Having used every Mavericks beta since beta 1, including the GM, as well as the final version, I can quite confidently say that everyone should upgrade straight away.

Whilst the many betas of Mavericks have had many bugs, the GM seemed to do away with almost all of these. For example, in every beta before GM, I suffered from an awful bug whereby you couldn't actually put the Mac to sleep - it would have to be shut down, since clicking Sleep or closing the lid wouldn't do anything. This was fixed along with many more bugs in the GM.

With my poor internet, I was considering keeping the Mavericks GM for a while, since I saw no incentive to update - there wasn't any problem that I was hoping that the public version would fix1.

It would appear that Apple's done it right this time, using the GM as the 10.9.0 and the public release as the 10.9.1.

In conclusion, I believe that people should upgrade from Mountain Lion to Mavericks without hesitation - there's no massive bugs from what I can tell, and I see no major reason for Apple to expedite the release of 10.9.1 to fix a serious problem.

1 (unlike my experience with the Mountain Lion beta - the public release couldn't come soon enough)