I also keep plenty of tabs open for things that I'm monitoring or want to get back to but appreciate that browser constraints force me to go through the tab backlog and either deal with the tab now or save it as a bookmark for later.
In any case, he could use Sleipnir 6. It's got your hundreds of tabs open market cornered.
Also, bookmarks aren't quite as ephemeral as tabs, so there are different workflow implications.
And if you are a professional one, you have less than 10 tabs opened because you are focused, and know what you are browsing.
Opera 12
Chrome and Firefox might have more dev time thrown at them, but when it comes to being well-engineered they have a LOOOOONG way to go yet.
My main point was really that the article linked is a silly hacky workaround to a problem that would not exist in the first place if Chrome and Firefox were well written software.
However as of late I've been trying to keep total count under 20. Though it's often quite difficult.