"ClickToPlugin is a lightweight and highly customizable extension that prevents Safari from launching plug-ins automatically, resulting in faster browsing, reduced fan usage, and increased battery life. It replaces every plug-in object by an unobtrusive placeholder that can be clicked to load the embedded content. Further, it can replace many plug-in-based media players by Safari’s native HTML5 media player." Installed.

"In re­cent re­leases, Sa­fari has been re-ar­chi­tected, with some of the work farmed out to a thing called “WebProcess”. This doesn’t seem to be work­ing out that well." Much as I was excited about Safari 5's re-architecting, I must admit: I've seen everything Tim says, and it's driving me nuts.

As recommended by John Gruber: replaces video flash with HTML5 equivalents in Safari. Nice.

"Use and create Delicious bookmarks from the Safari web browser" - with a single keyboard shortcut. My main reason for sticking with Firefox was its Delicious integration, but if this is any cop, I think I'm save from terrible memory leaks for the future.

Web Inspector gets an overhaul; it's looking pretty nice, now.

"The mouse is a continuous pointing device; the finger is discontinuous. That’s a profound difference that I wish I were able to clearly understand and explain." PPK on how MobileSafari responds to Javascript's mouse actions.

"This little hack adds find-as-you-type to Safari, Apple’s OS X web browser"

"GreaseKit is successor of Creammonkey. This software adds Greasemonkey-like user scripting to Safari, Mailplane, Diet Pibb.app and all WebKit applications." Looks good.

It is poor coding to access style/layout information repeatedly during the loading cycle of a page, because in order for the engine to supply you with an answer, it has to ensure that its layout and style are up to date.