Please put your suggestions on http://websig.wetpaint.com/

Web 2.0 Design Elements: rounded corners, gradients, diagonal hatch backgrounds, stripe backgrounds, Web 2.0 Color, large colorful icons with reflections and drop shadows, large fonts over 15 pixel, glossy 3-D elements, apparently random highlights and call-outs in text, a supermarket sticker, web floor effect, and beta sign.

Web 2.0 Techniques: Rich Internet Application (AJAX), CSS, Semantically valid XHTML markup/Microformats, Syndication and aggregation of data in RSS/Atom, Weblog, Mashups, REST/XML and Webservice APIs.

Web 2.0 Trends: Social networking systems like FOAF and XFN, Tag-based folksonomies in Blogs and Wikis, Weblogs, Linklogs, Podcasts, and RSS.

Web 2.0 Site Design Trends

Search Trends: Vertical Search, Social Search, Video/Image Search, Blog/Wiki Search, and SEO/SEM.

Browser Trends: IE / Firefox / Opera / Safari

Internet Marketing: Email Marketing, Video Marketing.

Digital Entertainment: Gaming, Music, Movies, News.

Development Trends: ROR, LAMP

Content Management System Trends: File-based VS Database-driven; Personal VS Enterprise.

Web Metrics: Web Analytics, Business Intelligence, Data Mining, Data-warehousing

E-Commerce: Micropayment, Wireless transactions, Mobile transactions, Shopping cart.

Where 2.0: Pushpin App, User-generated Mapping Data, GeoRSS, WFS, WMS, Web Mapping Mashup, and Geo-spatial technologies