I'm pretty sure the total time depends on which webpages you open. Also please note that this is for Firefox nightly (8) only. This might also be true for FF 6

I'm pretty sure the total time depends on which webpages you open. Also please note that this is for Firefox nightly (8) only. This might also be true for FF 6 and 7 but nothing before that. Memshrink enhancements have only started at FF 6 (which is not yet released as stable, but soon)