Online Aggregators

I'd like to represent a list of online Aggregators with their advantages and disadvantages:

Bloglines

Advantages:

• all major browsers supported (e.g. Netscape Navigator, Internet Explorer, Firefox)
• user-friendly especially for beginners
• free, web-based aggregator
• easy registration
• no advertisements
• contains its own directory of RSS feeds of thousands of websites
• personal email account for subscribing to newsletter emails (optional)
• allows privacy adjustments for personal blogs
• allows saved searches
• mobile version available
• 10 languages supported
• additional add-on tools for automated blogrolls and subscription buttons

NewsGator

Advantages:

• free (consumer-standard version)
• provides personalized news channel
• allows translation of RSS articles into email format
• synchronization of feeds in several devices possible
• browse and search feed capabilities save time on surfing
• allows keyword filtering
• blog headlines
• button-click automatic subscription to news feeds

Disadvantage:

• Outlook-based thus limited to Windows

My Yahoo

Advantages:

• Free web-based aggregator
• user-friendly
• customizable home page design
• button-click subscription to RSS feeds
• built-in directory and search tool for feeds
• wide variety of feeds e.g. news (science, technology, local), weather
• connects to all Yahoo features and services

Disadvantage

• banner advertisements

There are also lightweight RSS aggregator extensions which are actually plug-ins to existing internet browsers. An example of which is

Sage aggregator

Advantages:

• free of charge
• beginner-friendly
• reeds both RSS and Atom feeds
• allows feed discovery
• can be assimilated to Firefox bookmark (storage and live)
• allows OPML feed lists imports and exports
• customizable style sheets
• supports a wide range of locales e.g. Catalan, Italian, Japanese, Spanish, Korean, Polish, Slovenian, etc.
• easy installation

Disadvantages:

• good for about 12 RSS feeds
• limited use to Mozilla-Firefox and Mozilla-Firefox supported browsers