So this came up (again) on STYLE-899 and it might be a good time to decide how artist credits like X (duet with Y) should look like.
My preference would be that a credit like “Alice - Song (duet with Bob)” would become “Alice with Bob - Song”, but do others think the “duet” part needs to be preserved?
I personally would lean toward preserving “duet” because not every “with” artist credit is a duet, but that creates the problem of how to preserve it.
One method I have seen (and used) is to get creative with the join phrase boxes, creating something like "Alice (duet with Bob) - “Song”.
I see no problem with using " duet with " as a join phrase.
Well, it’s kind of ungrammatical, no? “Tony Bennett (duet with Lady Gaga)” or “Tony Bennett in duet with Lady Gaga” or something like that sounds ok, but “Tony Bennett duet with Lady Gaga” seems just like broken English to me.
We can add the in if without it it’s wrong.
But duet is important.
Exactly. That’s why I mentioned adding parentheses in the join phrase fields.
What I usually do when I encounter these is the following…
Alice [with Join phrase: " (duet with "]
Bob [with Join phrase: “)”]
Shows as
Alice (duet with Bob)
I was curious how digital music services handle this, so I did a quick search on Amazon: https://www.amazon.com/s/?url=search-alias%3Ddigital-music&field-keywords=“duet+with”. (I tried to check iTunes and Google Play too, but didn’t see a search mechanism without and account.) Here’s a summary of the top 50 track results:
Let’s bump the topic, since STYLE-899 is still open and it’s also an important aspect for me.
First I think, we should keep the credited joining phrase/word/type of the release anyway.
There might be a difference meaning for the used phrase. “Duet” often means the artists are somehow equivalent involved (e.g. fifty-fifty, or near counterbalanced of Alice and Bob). “With” often expresses that there is a leading artist (Alice), supported by Bob. “Featuring” can mean anything (but should never be used as replacement for other types).
Of course, often the used joining phrase/word/punctuation of a release doesn’t seems to have a qualitative and/or quantitative meaning but it should not be our aim to decide this.
The second question is how we put it into MB, also in a good grammatical style and not in a broken English (or the language used for the release).
IMHO there are mainly two cases.
First case, where both artists are credited on the song. This is typically on Various Artists compilations, but also sometimes on releases of a specific artist. Here, I think, it’s the best way just to use the artists credit like it is, with the given phrase/punctuation mark. I would not modify anything here, even if it’s a kind of broken English.
Second case, where the release artist (first artist) is not credited on track level. This is often on releases of a specific artist, where only the second artist is used on track level. Often the second artist is credited in brackets, where I prefer to kept/use the brackets in the artist credit join phrase (like @Lotheric described it above). It might also be possible here to distinguish if the artist credit (including the brackets) can be clearly seen as separated artist credit (e.g. written below the track title, or in different font style/weight) or if it’s just in the same style as the track title.
If there is no printed join phrase/punctuation mark – but only the words “duet with” – we should add something to not have broken English. Whereas “in” and adding brackets would be proper ways, I prefer just to add a comma (e.g. Alice, duet with Bob).
P.S.: If there is just the word “duet”, but no “with”, we have another case where I tend to credit as it is and not to add “with”.
P.S.2: What is valid for English “duet with” should also be valid for other languages, e.g. “Duett mit” in German.
@NeroA big vote “yes” from me here. What is on the cover is king. That is what the artist wanted.
I think this is one of those where “broken” English is acceptable usage. Not everyone walks around with grammar books out. That is why you see it as “Tony Bennett duet with Lady Gaga” on the album cover. 'cos this is 'ow we speak, innit. Grammer rulez are for the school room as the language mutates in common use.
I find it funny that the Style Guidelines here at MB have sent me back to my schoolbooks from the last century as they can be a little too strict at time. 
I can only speak British English and this site is re-teaching me my own language some days. 
The “in duet with” is just a little bit too formal and not really used in my experience. It is more common to see it without the “in”. Almost to the state that including the “in” makes it look odd to this Brit.
It’s that verb \ noun thing ain’t it? “This is a Tony Bennet duet with Lady Gaga” and “Tony Bennet is in duet with Lady Gaga” are both technically correct English sentences. I think. Or at least this Brit recognises them both as correct. But I see that second one as a bit overly formal and posh.
This is perfectly correct IMO too! The problem is that what we’re saying is “The artist here is Tonny Bennet duet with Lady Gaga”, which sounds just… off (compare with “The artist here is Tonny Bennet in duet with Lady Gaga”)