i've used both windows and linux machines for a long time, before switching to a mac a year and a half ago, and they both offer multiple lines of rows in most cases.
windows isn't my idea of "user-friendly" or "elegant" interface, and the same goes for KDE (which is like windows-on-steroids). gnome might be a little more elegant -- to the point of being austere.
for text document like applications i definitely don't think it's a bad design decision for the use case of being able to see ALL my documents that i have open with a quick glance.
multiple rows of tabs aren't the way. having more than one row of them simply destroys the metaphore, having the rows move according to which item is selected destroys consistence, and (last but not least) it severely impedes keyboardability.
again, these are apple UI _guidelines_ not words from god you must obey.
1. steve jobs is god -- at least, don't tell him he's not, he might be upset ;) 2. note how programs that follow the spirit of the guidelines (give or take a pixel) end up feeling native and integrated to the system. the current tab appearence is _not_ the one prescribed by the HIG, yet they hold to the spirit. two rows of tabs break the spirit of the rules themselves (predictability, consistence, keyboardability to name a few). -1 all the way for me.
allan stated below that he will be re-working things for 1.2, so i'll say no more on the topic and just wait for the changes to occur...
I'm pretty sure allan will do the Right Thing, whatever it is… and I think he's already got some ideas, he just doesn't want to disclose them ;)
ciao,
Domenico