This has been what I've experienced for more than just the latest versions. In personal usage the crossover between Chrome and Firefox has always been in the neighborhood of 20-30 tabs. Past that. Chrome has always seemed more sluggish (and less usable, given how tiny the tabs get).
Likewise. I typically keep open a large number of tabs, opening a pile of links at once and then going through them during the working day. At any one time, I tend to have a hundred-odd tabs open.
Although to be fair, firefox isn't too happy with that workflow, either - but I blame that partially on flash and javascript.
