Has anyone really ever noticed much difference with any of these betas? OSX 10.9 just runs pretty **** and sluggish no matter for me. A few random bugs come up or disappear with the betas but nothing major seems to be fixed or worked on. The fact that it's the same non descriptive list of "changes to" they give every time rather than specific changelogs gives me little hope to that much is actually changing, and that most of it is very very specific problems only few experience, or that is related to other big brands such as HP, DELL etc that they are fiddling with.
1) You shouldn't be noticing "big" or "major" changes in point fixes. These are not a move from, say, 10.8 to 10.9. A version release is when you, the end user, should see "big" changes.
2) If your Mavericks system is slow/sluggish - you should consider backing up your data via timemachine, do a fresh install, then import your data. Unless you have an ancient system that has a small amount of RAM, or possibly a failing HDD/SSD (and/or all three or some combination), or have borked your system folder in some way...Mavericks should be running like a champ for you. Mavericks, on my 4670K system, is ridiculously snappy...much more so than Windows which I, sadly, sometimes require.