its not the length that counts... title must depend on the content of the site. it must be meaningful and related to the site.
A related title that is 500 characters is not going to be counted normally. Google sees that as spam.
Go to Google and do a search for your keywords. Look at the results and you will see the searched words highlighted in the title of the various results. Do this a few times and draw your own conclusions. You don't have to ask for advice on this, just look at Google's results where you can see what they do with regard to this.
And the site name may contain vital keywords too. It's important to go with your gut instinct on how long is too long in these cases. Reading it back to yourself can help. If it takes half an hour to do this, you know you're in trouble, heh!
I think it's best to keep it as short as possible. Just stick to the keywords. And don't forget to stick with the content of the site, too.
In the past I've tripled the amount of traffic a page has received by including words that tie in with the site. With that said, it can be hard to create a title that is optimised towards both the search engines and your users.
So a good way to write your title is like "KEYWORD PHRASE - SITENAME" instead of "SITENAME - KEYWORD PHRASE" Put the keyword phrase first.
Sometimes I wonder.... I was being sarcastic if you didn't catch that. I always put the site name to the end. If nothing else it is most convenient to visitors reading and having titles that all start the same doesn't look so good.
60 characters is good, but less is better in my opinion. Every page should be aiming at just the one topic, to maximise relevance in a search engine's eyes. Your home page should be telling the reader what your website is about, yes - but it should do it in an extremely succinct manner - and that includes the page title.