Bora Zivkovic from A Blog around the Clock mentioned that Discover Magazine just started with a collection of top science blogs. For me that post was an incentive to updated my list of science blog portal and aggregators.
Since I think the list is far from complete I thought it wisely to post it here to and see if the comments will lead to some useful suggestions:
The Academic blog portal http://www.academicblogs.net/wiki/index.php/Main_Page
A wiki that lists a large collection of academic blogs.
Discover Blogs http://blogs.discovermagazine.com/
Freshly starting collection of science blogs at Discover Magazine. It hosts one of the most popular science blogs Bad astronomy.
Nature Blogs http://blogs.nature.com/
A collection of blogs run by Nature. A really interesting post on one of the Nature blogs was their investigation of the scientific blogosphere
Nature Network Blogs http://network.nature.com/blogs
A collection of some 80+ blogs run by scientists on the Nature Network.
Postgenomic, also from the Nature Publishing Group, harvests about 800 science blogs -including most blogs from the agregators mentioned on this page- and collects what is hot and what not at the moment. The full list of blogs covered is give at this website.
Research Blogging http://researchblogging.org/
A collection of blogposts discussing peer reviewed research
Perhaps the best known collection of science blogs (including most of top science blogs reported by Nature) which has grown to syndicate some 70 science blogs.
Scientific American Community Blogs
Just ceased to exists.
Scientific Blogging http://www.scientificblogging.com/
One blog platform hosting many bloggers on various scientific subjects that can be followed with a few feeds per subject.
As you can see I have left out the science blogs at journals such as WIRED Science, Time, CBC, NYT and Correlations, I am looking for larger science blogging communities, aggregators or portals.