Replacing the T with a space is explicitly allowed by ISO 8601 if context makes it obvious that the date and time belong together. I prefer the version with space for many purposes since it's easier for humans to parse at a glance.
You are correct that time offsets are used instead of timezone names. The most obvious reason for that is that many names are ambigious (EST is either UTC-5 or UTC+2, depending on whether you live around the US or around Egypt).
Point of pedantry: RFC 3339 allows replacement of the T with a space; ISO 8601 merely allows its omission (and that only by mutual agreement of all parties to the information exchange).
Comments
What? Isn't "2015-06-29 15:44:21 EST" the ISO format? Can't think of anything more relevant.
ISO 8601 format would be 2015-06-29T15:44:21-05:00.
Replacing the T with a space is explicitly allowed by ISO 8601 if context makes it obvious that the date and time belong together. I prefer the version with space for many purposes since it's easier for humans to parse at a glance.
You are correct that time offsets are used instead of timezone names. The most obvious reason for that is that many names are ambigious (EST is either UTC-5 or UTC+2, depending on whether you live around the US or around Egypt).
Point of pedantry: RFC 3339 allows replacement of the T with a space; ISO 8601 merely allows its omission (and that only by mutual agreement of all parties to the information exchange).