So we have version 1.5.5b and 1.5.5c already (and then 1.5.5d on Jan 1). I'm really glad I didn't adopt this one! The changes are not major but I suspect a lot of people will be happier with the 1.5.5c version. The over zealous sanitizer has been quelled – I ran into this with the one live 1.55 cart I've worked on. I'm used to being able to add a bit of formatting in on the category or products names but the santizer wiped that out along with a number of small other bits. The patch for that particular problem was simple but now they've made the appropriate changes in this version. I suspect we haven't heard the last of that though. That is definitely a stay tuned type of situation.

I'm going to continue to install or upgrade to only 1.5.4. I suggest giving it more time before relying on 1.5.5.

Mailchimp is changing it's API as of Dec 31, 2016, so be sure to pick up the latest files from the zencart plugins or if you have one of my templates, contact me to have it upgraded (my version is different from but based on the zc plugins version).