In writing a report for an illuminea client, Traffix Diameter Systems , I wrote the following about the new Modified Phrase Match and Exact Match:
“The low-volume keywords (ex.: misspellings and 4-word phrases) have been paused to allow them to be targeted by other keywords set on phrase match targeting.”*
*Phrase match did not previously target misspellings (or accents or abbreviations), so it was necessary to add misspellings as separate keywords, which resulted in low-quality scores since the landing pages did not also misspell the keywords.
Alternately you could target these keywords using modified broad match and broad match targeting, but this meant lower CTRs since the same ads would have to target a wide, diverse audience.
Google has, starting May 1, changed the default nature of phrase and exact match keywords to include these variants: misspellings, singular/plural, stemming (swimming will also match swim), accents and abbreviations.
So you can achieve high keyword quality scores on phrase-matched keywords without worrying about writing ads that both appeal to your regular audience and your misspellings demographic with modified-broad-match ad writing.
P.s. Anyone who doesn’t want this can opt-out via the Campaign settings selections page.