Disadvantages of using U+2028 LINE SEPARATOR as your newline character:

• Almost no programmers have heard of it
• Few programs know how to deal with it correctly
• Yet another contender in a field already split between CR, LF, and CRLF
• Uses three bytes in UTF-8
• Not present in any non-Unicode character encodings

Advantages:

• Insane amounts of pedant-nerd cred