> Aren't they only able to collect meta-data on the conversations and not see any of the texts themselves? Also, no ads yet, so that's a win for me.

Ha!

I so don't trust Meta.

I wouldn't put it past them to double encrypt your messages and split it off at the server.

Edit: Clarification: Encrypt your plaintext twice, append it, split it off at the server. Send your message on to recipient and decrypt it themselves for their processing enjoyment.