Just noticed this had changed when I went to check my usage earlier, very welcome news!
Considering the recent promotion of half price essential packages + unlimited downloads for new customers, I felt a bit miffed paying more for less. Thanks TalkTalk!
They didn't, it was 40GB with the essentials package with an optional boost of another 40GB for an extra £5 a month. But now you get unlimited for the extra £5 or you'd still have the 40GB cap. Unless you're a new customer.