* My iMac's Activity Monitor (10.7.4) registers some really bizarre activity on such sites — for example, CPU activity related to Firefox seems to go berserk, sometimes indicating 70-80% user usage, with occasional bumps up to 110% user usage (if that were even possible). User usage is normally in the 10%-20% range.
110% CPU usage is entirely possible since you have more than one core in your CPU. Given a dual core CPU that could represent 55% of each of the two cores, 100% of one core and 10% of another, or any possible combination thereof. On my old Mac mini with a quad core i7 processor a usage figure of over 200% CPU was not uncommon. Given the new iMac Pro up to an 18 core processor and the right combination of applications and tasks, over 1,000% usage could be the norm!
