Continuity mistake: Near the start of the show, Roz is in her booth at KACL and takes out her lipstick and compact - we see her uncap the lipstick. Then Niles comes in an Frasier reintroduces them, and we see her uncap the lipstick again.
Continuity mistake: Frasier is at the dining room table with Niles looking at Niles's childhood journal. He has his left hand ready to turn a page but in the next shot his hand is on the table, with no time for a natural shift.
Answer: It equals the record of James Arness of "Gunsmoke" for the actor who's played the same part on TV NOT in a soap opera. If you include soaps there are two main contenders - William Roache, who's been playing Ken Barlow in "Coronation Street" in the UK since 1960. Don Hastings has been playing Robert Hughes in US soap "As the World Turns" since 1960 as well.