When TextSecure removed SMS encryption there wasn't a clear warning about it in the what's new message, and as far as I can tell there was no deprecation period or warning to users who had been using it. You'd be sending encrypted messages before the update, and unencrypted messages after. For some reason they didn't link to their blog post[1] in the what's new message. It looks to me like they didn't want people to notice that they were removing a feature.
This lessens my trust in the creators and makes me hesitate to update the app since I don't know if they will change or remove features I do use in the future without warning. Hopefully they'll review their process so they don't scare more people over to SMSSecure.