Probably upgrade in the first couple days, but I plan to take a CCC backup image first, so if anything I use regularly breaks, I can revert and try again after a few point releases.
That's the key; make an image of your current system with Carbon Copy Cloner before you upgrade. This makes the upgrade zero-risk; if anything goes wrong you can revert without losing a thing.
Not to mention, it makes an excellent full backup in the unlikely event that your data gets damaged.