I discovered an increasing trend of Blog Aggregators ( Blog Lists have been around for a long time). Several sites come in this category- http://bigdatanews.com/ (which is a GreenPlum /AsterData sponsored site on Big Data) , http://mapreduce.org/ (which is a site on MapReduce that has an inbuilt blog aggregator but is more of a community website – I will explain the difference below) , http://www.r-bloggers.com/ (which is an excellent aggregation of 69 R Bloggers sites that is built by Tal and is currently not sponsored/independent) and http://smartdatacollective.com/ which is sponsored by Teradata and uses http://wordframe.com which is a paid software) and some others like http://www.biblogs.com/ (which is Adsense supported 🙂 ) and http://javablogs.com/Welcome.jspa (an aggregator on Java) (or even http://feministblogs.org/).
CMS Based Blog Aggregator
CMS Based Blog Aggregator/ Community Site
CMS Based Community Site with an inbuilt Blog Aggregator feed
I am noting blog aggregator as a distinct website that pulls in automated content from RSS feeds , may or maynot be moderated, and usually revolves around a certain domain or topic. It is slightly different from community websites which have Lists of Blogs as part of many other features, and boutique collection of blogs like http://www.b-eye-network.com/blogs/index.php
and Intelligent Enterprise ( http://intelligent-enterprise.informationweek.com/blog/index.jhtml) as they have selected authors and have more than Blogs as their featured content including News etc. Since community is a buzz word- many websites claim to be community websites while retaining the look and feel of a CMS- Blog Aggregator.
WordPress Enabled Blog Aggregator
Anyways, if you have a WordPress Installation- you can create a Blog Aggregator for free. Basically there is a wordpress-plugin called FeedWordPress http://wordpress.org/extend/plugins/feedwordpress/
Doing so you can simply addin as many RSS feeds as you like –
(see a screenshot below).
Of course – you can use Twitterfeed to create a Twitter Aggregator/ Fire Hose that simply pulls in Post Titles, and can link them using Facebook-LinkedIn-Twitter apps to your RSS feed of the aggregated website. 🙂
Building a website /content aggregator is just a few clicks away and free for anyone with a website and some passion for a topic. It is really free and painless 🙂
DECISION STATS 
I think you cannot use the WordPress plugins for WordPress.com hosted blogs (which Decisionstats has been for anti-spam, anti-hacking reasons)
But you can do the following- subscribe to a blog using its RSS feed and auto-forward using rules to the post by email feature of WordPress.
Ajay
The D-I-Y Blog Aggregator is a fine effort at CMS. Initially I thought you referred to a Blog Directory e.g. on Technorati, but your idea is different. Do you happen to know if WordPress.com offers that nice FeedWordPress plug-in, or if it is only for paying WordPress.org blogs? I sure would like to construct my own Blog Aggregator too! Thank you for the idea!
P.S. There’s a Twitter feed aggregator that uses predictive analytics and network analysis to derive some actual meaningful content from the 10 to the order ??? number of Tweets floating about. I’ll forward the name and URL once I relocate it.
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