Answer: optedin

AnswerCrossword Clue
OPTEDINDecided to join
OPTEDINChose to participate, as with an e-mail list
OPTEDINDecided to participate
OPTEDINChose to play
OPTEDINChose to participate
OPTEDINAgreed to take part
OPTEDINDecided to enter
OPTEDINChose to join
OPTEDINChose to take part