Nicely written article with a good synopsis of what constitutes an effective page title. However there were a few things I found to be interesting.

page title should be short and concise (unless you want it’s broken at the end) - While I agree with this for the most part I don't think I'd worry too much if a title tag is cut off. I agree it should be as concise as possible but we are working with a very limited amount of characters that will be shown in the results...I like to work and focus on an ideal number of words that I would like to get in the tag, say 10-13 using my targeted keyword phrases and eliminating any extraneous junk instead of worrying about whether or not the tag will get cut off. Do your best to ensure that it looks good in the results even if it is cut off but even the best title tags on well optimized sites may get cut off.....I wouldn't limit myself.

each page title should be unique and the unique part should go first (if a visitor keeps several tabs from the same open, he should clearly see what each tab is about) - Are we saying here that company / business names should never, ever be first? While I would agree that using the company first isn't always ideal I think in some cases it can help your first main target, increasing clickthrough.

A global title change (applied to all or large number of pages) is most likely to trigger some kind of penalty (sudden Google referral traffic decrease). So my advice is: change 1 -2 titles and wait 2-3 weeks, then change other 1-2 titles, etc - I would love to hear others opinion on this as I have never heard of this nor seen it happen. It doesn't seem to make sense to me that Google would penalize a site who happens to change all of their titles, or many of them, at the same time in an effort to improve their site. I'm not talking being all spammy or anything like that, just a genuine effort to optimize ones site. Personally I don't think it's a good idea to be constantly changing your title tags because doing so is basically the same as a dog trying to chase his tail, your efforts will never sink in with the search engines. Research is vital.

Talking about Duplicate Title Tags:

Has anyone expirimented with the time that it takes for Google to recognize the replacement of a duplicate title tag? They stress duplicate titles are a problem in Webmaster Tools, and show you which pages they recognize as duplicate. Has anyone ever seen how long it takes for google to update the tools? Should give us an the long end of time before Google recognizes new tags.