The 6th edition, published by HarperCollins in cooperation with Heinle Cengage, appeared in bookstores and on Amazon in late 2008. It has a radically different cover design and a new, shorter name: Collins COBUILD Advanced Dictionary, but the content is almost identical to the 4th and 5th editions. Here are the main differences:
A few fairly useless new entries (e.g. Bluetooth, open-source) that you can look up on Wikipedia
The design is nicer, with better paper quality and more colors (see example pages)
Some illustrations next to entries (the previous edition only had illustrations in a separate section)
For some words, there are "Word Partnership" boxes which give common phrases (collocations) with the word (see example page 1).
There are also occasional "Thesaurus" boxes (with synonyms) and "Word Web" boxes (short paragraphs which discuss a topic, e.g. pollution, using many different words related to the subject).
While the book is quite good, the software on the 6th edition CD-ROM is the worst software dictionary that I have ever seen. Even the most basic features like search are either very slow or buggy. There are no phonetic transcriptions, there is no Word Bank, and the quality of recordings is horrible. This product feels like it was designed to make your experience miserable. Avoid the 6th edition, unless you don't have a computer and have to use a book dictionary.
The rest of this review is based on the fourth and fifth editions of the Collins COBUILD Advanced Learner's English Dictionary.
感觉这个版本跟那个柯林斯美版的差不多，界面都一样=,= 不太友好，没法自定义界面大小什么的。 看来他们这个词典的CD没打算认真做了...