I'll just add an "Amen!" to all the descriptions preceding my post: Safari 6 *IS* dysfunctional and a step down, not up, from Safari 5.
I downloaded Safari 6 the day it was released, use my Macbook 10-12 hours daily in my business, and have yet to experience anything snappy, zippy, or fast about the new Safari. H/W specs of the "TARDIS", for whom it may concern:
Model Name: MacBook
Model Identifier: MacBook3,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2.2 GHz
Number of Processors: 1
Total Number of Cores: 2
L2 Cache: 4 MB
Memory: 4 GB
Bus Speed: 800 MHz
Boot ROM Version: MB31.008E.B02
SMC Version (system): 1.24f3
Serial Number (system): (not disclosing for this post)
Hardware UUID: FA74C376-E209-53BA-BBE0-D51283BC69A6
Sudden Motion Sensor:
State: Enabled
We run Mac OS X 10.7.4 (Lion), with no immediate plans to buy Mountain Lion -- in two weeks' research re the Safari 6 issues, we've seen no conclusive proof the new browser's speed and handling issues are improved by an ML upgrade.
The only plugins used here are those standard with the system; no extensions; and we've never needed nor wanted any browser but Safari, from our first iBooks running Jaguar, to Powerbook G4 with Tiger, and now, the MB with Lion. Frankly, until we d/l'd Safari 6, our user experiences were pretty much flawless.
Now, not so much.
Apple engineers/developers need to note seriously the thousands of complaints scattered across the internet -- here, at social media sites, at Google users' forums, and at the various Mac users' forums. There is undoubtedly a problem with Safari 6 for a large and vocal number of users, if they'll only bother to examine the evidence.