I have had the opportunity to read Karl Swedberg and Jonathan Chaffers book Learning jQuery : Better Interaction Design and Web Development with Simple JavaScript Techniques and I recommend the book for designers as an introduction to jQuery and JavaScript and as a reference for more experienced developers who wants to dive into jQuery JavaScript Library.
Both Karl Swedberg and Jonathan Chaffer are Web Standards Advocates and all of the examples more or less comply to Progressive Enhancement, making jQuery and JavaScript adding more behavior to an already functioning web. It is important that JavaScript is presented this way, as a lot of older developers and designers who saw the JavaScript-savvy webs that where built pre-millenium and have in memory pages that only work on specific browsers and so on.
Learning jQuery does what it say, it helps designers and programmers to enhance their webs with jQuery and JavaScript. I recommend this book both for designers looking for adding skills to their portfolio and for developers who wants to learn JavaScript the jQuery way.
If you are interested to read more on front end architecture we cover this on The Frontend Blog
