Q: Worst update ever - my computer loads slowly, is incredibly sluggish, and totally unusable.

What year Mac do you have? If you have an old mac, chances are that your computer is not meant to handle it. I had the same problem with my iPad when I upgraded to iOS 8.

I have to agree. Yosemite is stunningly useless. Just glad I had a Mavericks backup with SuperDuper. Glaciers travel the entire length of Yosemite Valley faster than we can get Yosemite installed and running.

Hhmmm... I have a Macbook air (same ye as yours) and my doesn't seem to have problems with the update... Odd

I experienced very slow performance for the first day but then, after running Utilities and deleting some apps, performance improved.  Try that and see what happens.

i would have agreed with you yesterday after I did the update. I had to update my iWork's apps. I shut down as I thought all the updates were done. This morning when I turned on my MBP it finished updating something. I was able to finally finish the remaining apps & now it seems to be running much faster.

Must be your Mac. I'm on an early 2009 iMac and Yosemite runs better than Mavericks did. It's very snappy.

Boot times will be slow in the beginning, and Spotlight is probably indexing your drive.

How much RAM do you have?

I have been running the 10.10 public beta, but I did find that after updating to the final version it ran better after a second reboot.

i installed it yesterday on my 2012 MCB.  I did a clean install and restored from my Time Machine backup.  It seems incredibly fast to me.  No glitches at all.  I'm not sure I care for the new icons in the dock and the new font will take some adjustment but so far, so good.  I'm very pleased. 

I fully agree with you!! The worst update ever! My iMAC is bought early in 2012... And without more thinking i clicked the upgrade to Yosemite!!! AND the mess !!! So slow, so disturbing machine! I cannot work any more! HOW CAN I RESTORE the iOS as it was 3 days ago?  I WANT to DISAPPEAR this YOSEMITE, NOW!!! a) What can Id do? Can I do it without formatting? b) Do you think that soon we are going to have the next version of Yosemite and the silly behaviour of YOSEMITE will be corrected?

Don't shout. Yes, we will be seeing an update soon. Version X.1 is always released just a few weeks after the initial release. Apple tries to repair the most disruptive bugs in that first update, and does more finetuning in the second, which usually is released about two or three months after the initial release. That's the usual routine.

On some Mac's people seem to have performance issues like yours. I understand your not happy, but I suggest you'll be patient some more and update when 10.1 or 10.2 comes out. When it does run smooth on your machine, you'll find out it's the best upgrade (it's an upgrade, not an update) since many years.

Do as Canyonlight wrote in the fourth entry of this topic. Just use you backup and go back to Mavericks and wait it out. Nothing wrong with that. Upgrading is not a necessity but a choice.

I certainly wasn't shouting. I'm not annoyed, just disappointed and frustrated. If I have to wait 2-3 months for a usable OS, I'll wait, as I'm not a techie and haven't the remotest idea how to go about reverting to Mavericks. Until then, I guess I'm stuck with my old Windows laptop.

He was not replying to you.

Pete

The usual and safe routine before upgrading to a new OS is making a full cloon-copy of your harddrive to an external harddrive. Most folks heren are using Superduper of Carbon Copy Cloner to do the job. You install the new OS after that and if you encounter any substantial problems that can't be resolved at once, you simple copy the cloon  back to you main harddrive. You don't have to be a techie to do that. The apps work plain and simple.