I explain this in a comment that's a bit further down the page but here it is in a nutshell:
* You're right that this is very similar to our previous offering. At its core, the encryption logic is the same.
* While both libraries offer an object which will encrypt your data, that's literally all our previous offering did. New helpers used in conjunction with data attributes eliminate the need to write custom onSubmit handlers, making your integration far simpler.
* We host the JavaScript, making linking directly to it an option.
These things make our JavaScript library substantially easier to use. That, plus the fact that we now recommend Braintree.js over Transparent Redirect motivated us to rebrand it.
* You're right that this is very similar to our previous offering. At its core, the encryption logic is the same.
* While both libraries offer an object which will encrypt your data, that's literally all our previous offering did. New helpers used in conjunction with data attributes eliminate the need to write custom onSubmit handlers, making your integration far simpler.
* We host the JavaScript, making linking directly to it an option.
These things make our JavaScript library substantially easier to use. That, plus the fact that we now recommend Braintree.js over Transparent Redirect motivated us to rebrand it.