What is a library mod? Is that a directory? Or something more specific to books?
Reviews is a directory by definition. For example the difference between a business directory and a reviews directory is only, that the latter has ratings and comments.
Currently I see a lot of demand for a full blown reviews addon for XenForo, vbulletin and IPB. Similar threads are to be found at all 3 communities.
The Library add-on is designed so you can edit pages from the frontend just like writing a forum post, with text or images or both. Like a forum message images can be uploads or URL links.
Articles can be single or multiple pages, which paginate, so chapters or series are supported.
They have TITLE, CONTENT, and PREVIEW SNIPPET (For listings). Author name and date is displayed. Author avatar is displayed, but there is also an alternative small addon toi display a small graphic on the listing of author's choice.
Articles can optionally link to a forum thread for discussion, keeping comments in the central core, the forums, and with the better quality functions of forum messages over blog comments.
Articles are contained in one or more Libraries which are subject to usergroup permissions.
Libraries are nodes which integrate with the node tree. A library can contain any other nodes including Libraries, or be the child of any other type of node including Libraries.
New Articles show in "What's On" just like threads.
Right now current development is on the design of Library listings pages
to have sticky Articles/ Latest Articles, and numeric or A-Z sort.
Also Likes on Articles.
The next stage (no. 3) is to bring in a template editor so Admins can create different kinds of Articles according to the needs of the site. Instead of a one size fits all Review you'd make it fit the types of things your site reviews.
As well as the basic Title, Content, and Preview, the admin could add fields to create a Review Article,providing boxes for technical details of a gadget, or date of manufacture, or publisher, or an image or several, or URLs, or links to media, or any other other specifics that make a Review informative in a structured way, and appropriate to the site.
In this way a submitted Review would be displayed in a consistent way with other Reviews of the same type of item. But not in a standardised way so your Reviews are just like evryone else's. Not one size fits all.
There could also be a different format Reviews on the same site. Book reviews need to show different sets of info to music or film reviews, or software reviews, cars, gadgets, events, artwork, websites, celebrities ... anything. But the admin would ONLY have the types of format they needed for their own site, so there is no bloat.
All Reviews could be stored in one Library, or in several themed Libraries, perhaps all contained in a mega Library. But Libraries can be stored in an XF Category or displayed as part of a forum. (Remember any Article/ Review can link to a forum thread for comments.)
The flexibility is very high. Creating templates with an editor at admin level also means an Article can be a Quote/ Website directory item etc. Almost any kind of object, created item, or event could be described and analysed. Galleries are possible (they already are but they would be more formally structured).
Users will be able to share templates for types of Articles/ Reviews if they do not want to create their own.
It would not be difficult to add Ratings.
The flexible template editor could provide a personal album or blog to link off the Profile page.
Part of the planned roadmap is also to support members having their own personal Library to display their own Reviews/ blogs/ Articles, their own magazine (Article collections in a series), timelines you name it. This would be useful to collect one Reviewer's work on one page or series of pages with other info about them.
But some review systems will want integration with Amazon to get feeds or connect with the affiliate system.This will need different treatment.
This would require a set page template to work with Amazon's page fields. This Amazon derived Review would need to be an independent addon that works with the Library foundation.So it benefits from all the considerable features of Libraries and Articles, but uses a page layout designed to draw info from Amazon and optionally work as an Amazon affiliate.
It's all about admin choice really. Have just the fixed type of Review that works with Amazon.
Have fixed type Reviews but also your own design or someone else's for other types of Reviews. Plus if you like other Articles for text and pictures. Plus authors having their own Library collections on a page (their Reviews or other work) and any part of this can link to a forum thread.
A number of XF people are already interested in both types of development.