No harm in using key phrases in titles, but you should be careful not to overdo the use of key phrases.
I do article rewrites for some canny US domainers occasionally. They usually specify that they want the key phrase in the title, and once again in the document body for every 300 words, ie. they like about 250-300 words to separate each use of the key phrase, and if it's not in the title it wants to be in the first or second sentence of each piece of body text.
Don't forget that the search engines use the meta description when they list the site in a search, so you want that to "look right" and pertinent - and you want a different set of meta tags for each page, or the spiders will assume the pages are all "samey".