Uses Gruber's edge cases. My additional tests use sentence case input. Incorrect output is highlighted. Show script runtimes.

Gruber’s Ideal Titles Gruber’s Perl Results source Gouch’s Javascript Results source Resig’s Javascript Results source
For Step-by-Step Directions Email someone@gmail.com For Step-by-Step Directions Email Someone@gmail.com For step-by-step directions email someone@gmail.com For step-by-step directions email someone@gmail.com
2lmc Spool: 'Gruber on OmniFocus and Vapo(u)rware' 2lmc Spool: 'Gruber on OmniFocus and Vapo(U)Rware' 2lmc Spool: 'Gruber on OmniFocus and Vapo(u)rware' 2lmc Spool: 'Gruber on OmniFocus and Vapo(u)rware'
Have You Read “The Lottery”? Have You Read “The Lottery”? Have you read “The Lottery”? Have you read “The Lottery”?
Your Hair[cut] Looks (Nice) Your Hair[Cut] Looks (Nice) your hair[cut] looks (nice) your hair[cut] looks (nice)
People Probably Won't Put http://foo.com/bar/ in Titles People Probably Won't Put Http://foo.com/Bar/ in Titles People probably won't put http://foo.com/bar/ in titles People probably won't put http://foo.com/bar/ in titles
Scott Moritz and TheStreet.com’s Million iPhone La‑La Land Scott Moritz and TheStreet.Com’s Million iPhone La‑La Land Scott Moritz and TheStreet.com’s million iPhone la‑la land Scott Moritz and TheStreet.com’s million iPhone la‑la land
BlackBerry vs. iPhone BlackBerry vs. iPhone BlackBerry vs. iPhone BlackBerry vs. iPhone
Notes and Observations Regarding Apple’s Announcements From ‘The Beat Goes On’ Special Event Notes and Observations Regarding Apple’s Announcements From ‘the Beat Goes on’ Special Event Notes and observations regarding Apple’s announcements from ‘The Beat Goes On’ special event Notes and observations regarding Apple’s announcements from ‘The Beat Goes On’ special event
Read markdown_rules.txt to Find Out How _Underscores Around Words_ Will Be Interpretted Read markdown_rules.Txt to Find Out How _underscores Around words_ Will Be Interpretted Read markdown_rules.txt to find out how _underscores around words_ will be interpretted Read markdown_rules.txt to find out how _underscores around words_ will be interpretted
Q&A With Steve Jobs: 'That's What Happens in Technology' Q&A With Steve Jobs: 'That's What Happens in Technology' Q&A with Steve Jobs: 'That's what happens in technology' Q&A with Steve Jobs: 'That's what happens in technology'
What Is AT&T's Problem? What Is AT&T's Problem? What is AT&T's problem? What is AT&T's problem?
Apple Deal With AT&T Falls Through Apple Deal With AT&T Falls Through Apple deal with AT&T falls through Apple deal with AT&T falls through
This v That This v That this v that this v that
This vs That This vs That this vs that this vs that
This v. That This v. That this v. that this v. that
This vs. That This vs. That this vs. that this vs. that
The SEC's Apple Probe: What You Need to Know The SEC's Apple Probe: What You Need to Know The SEC's Apple probe: what you need to know The SEC's Apple probe: what you need to know
'By the Way, Small Word at the Start but Within Quotes.' 'By the Way, Small Word at the Start but Within Quotes.' 'by the way, small word at the start but within quotes.' 'by the way, small word at the start but within quotes.'
Small Word at End Is Nothing to Be Afraid Of Small Word at End Is Nothing to Be Afraid Of Small word at end is nothing to be afraid of Small word at end is nothing to be afraid of
Starting Sub-Phrase With a Small Word: A Trick, Perhaps? Starting Sub-Phrase With a Small Word: A Trick, Perhaps? Starting sub-phrase with a small word: a trick, perhaps? Starting sub-phrase with a small word: a trick, perhaps?
Sub-Phrase With a Small Word in Quotes: 'A Trick, Perhaps?' Sub-Phrase With a Small Word in Quotes: 'A Trick, Perhaps?' Sub-phrase with a small word in quotes: 'a trick, perhaps?' Sub-phrase with a small word in quotes: 'a trick, perhaps?'
Sub-Phrase With a Small Word in Quotes: "A Trick, Perhaps?" Sub-Phrase With a Small Word in Quotes: "A Trick, Perhaps?" Sub-phrase with a small word in quotes: "a trick, perhaps?" Sub-phrase with a small word in quotes: "a trick, perhaps?"
"Nothing to Be Afraid Of?" "Nothing to Be Afraid Of?" "Nothing to Be Afraid of?" "Nothing to Be Afraid of?"
"Nothing to Be Afraid Of?" "Nothing to Be Afraid Of?" "Nothing to Be Afraid Of?" "Nothing to Be Afraid Of?"
A Thing A Thing a thing a thing