Originally and still a poker metatphor, 'all
in' has also come to mean a situation whose subject is unreservedly involved, without
qualification. Fully committed. In this sense the term "all in" is almost the same as its denotative opposite, "all out," as in
all-out warfare.
Example:
.
All in means you don't stop for Sundays.
All in means nobody can talk you out of it.
--
(from New York Times online, October 17, 2011):
Mr. Immelt’s remarks took on the tone of a halftime
pep talk. He said that with a clearer regulatory structure, an increased export base and an “all-in” business climate, the United States would be able to compete on a global front.
---Note that the Times used the term 'all in' with a hyphen separating the two words, which is customary when such a term is used as a single adjective. (Compare: "Frank is just
flat-out broke".) Also note that the Times put slightly
distancing quotation marks around the phrase in the above Immelt citation. This probably means that the Times writer recognized the phrase as a colloquialism, not yet fully acceptable standard written English, in this extended (non-poker) usage. Some grammarians (cf.
Strunk and White, THE ELEMENTS OF STYLE), object to ironic or distancing quotation marks on the theory that if a term or phrase is known to most readers, introduction or
contexting is not necessary. Most likely, though, the New York Times' elaborate style sheet does not forbid such use.