Got our by-mail ballots yesterday and will put them into the drop-box at Town Hall this afternoon.
In Massachusetts every registered voter can vote early, in person, or by-mail (which is essentially absentee) and every registered voter was sent an application for mail-in ballots. If you send in your signed application they mail you the ballot/envelopes. Then you complete your anonymous ballot, seal it into the inner envelope with your name/address/repeat signature and barcode identifier on it, place that into the postage-paid return envelope and either mail it in or put it in a drop-box. When it's received they open the outer envelope and verify the name/address info and signature on the inner envelope, and either accept the ballot or set it aside if there are problems. Accepted ballot envelopes go into secure storage until they can be opened and the anonymous ballots counted with all others; if it kicks out they inform you that there's a problem requiring your attention. If you request a mail-in ballot you can still vote early/in-person as long as your mail-in vote hasn't been returned. Your first accepted ballot will generate an entry in the voter rolls that negates any subsequent ballots you try to submit. You can check the status of your ballot online anytime.
If this is the wave of the future for all states I think it's a great way to participate in the process.