Comparative analysis

Advantages

The page for adding a blog to the "blogdex" was really simple and provided nice cues.
The use of the term "weblog" vs. "blog" sounds less geeky.
"Year ago today" features was fun and interesting.
Overall, the site design was clean and elegant. The author claimed to want to follow the Google model "Do one thing, and do it right." Overall, I think he succeeded, but...

Disadvantages

...(continued from above) the "one thing" neither completely matched his stated purpose nor was particularly compelling. It was difficult to envision how many tasks it could really support.
If the term "blog" is ever mainstream, "weblog" will have to change.
Overall, terminology was confusing; results from clicking links did not always match expectations.
Search feature should have been more prominent, even if it wasn't the main purpose of the site.
Search page instructions were lengthy and confusing.
The "next" and "previous" links at the bottom of the front page didn't give any indication of how many pages there would be to click through;
Easy to click on blog title expecting the tracking feature.
Not clear what "recent news" would link to (under "Information" in the sidebar). Expected news articles (or blogs?) sorted by date. It turns out that it is the author's blog.
Side bar contents changing between pages depending on context (which is a good thing in many ways), but it was confusing when items that were consistent across pages were not in the same place. On the other hand, it does make sense to see the most context-sensitive stuff to be at the top. Tricky problem.

Advantages

Google can search a wide variety of data sets (news, Usenet, web, and others).
The search dialog is very simple.
An advanced search is available for more advanced users.
The results are ranked by relevance/popularity.
The interface allows quick switching between data set while preserving the query
There is a built in spell checker.
A user's position in the search results is shown by red “o” in Google graphic, which is a good system status display.
The results show the key words in context, the page title, the URL, and page size.

Disadvantages

It is difficult to find the pages linking to a specific site. It is possible, but it is considered an advanced feature.
Search results include non-blog web pages.
It is not possible to get your rank. You can see how far down your page shows up on a specific search, but it might take a lot of work.

Advantages

Shows keyword in context, like Google.
The result display is nearly identical to google, down to the formatting and delimeters.
Sources are specific to blogs and blog-like media

Disadvantages

The "Top 40" doesn’t seem relevant. Many of the top sites seem domain specific. Is a guide to programming Ruby really in the top 20 topics discussed by webloggers? [Note: On closer inspection, it might be... it’s an incredibly funny programming guide, with cartoon foxes who smoke cigarettes.]
Top blog posts seem to mix languages (English and French), so many of the results aren’t relevant to speakers of either language.
There are a lot of different lists, but it isn’t clear what any of them do until you’ve looked at them. You would need to know all the site developer's language before using the site. i.e, “top news bursts”
Terminology is very confusing; somehow, “Most popular” and “highest rated” are different, but it is not clear why or how.
Daypop requires several clicks to switch between data sets (select new data set, press search)
The KWIC view does not effectively show context. The context is poorly parsed, so the keyword is often shown with unrelated bits from the next sentence or paragraph.

Advantages

Returned results are extremely timely.
Shows keyword in context with links to the result.
The result displayed are sorted with the most recent first, though this is easily resorted by authority (most inbound links).
Source is available with "link cosmos" which is all other blog posts that point to that blog.
Sources are specific to blogs and blog-like media.
Can search on URL of either a blog or other source, to find those linking to the URL.

Disadvantages

Some of the site's links (and features) don't go anywhere.
Some of the links in search results don't connect to anything.
Some of the names of features such as "breaking news" and "current events" don't make sense even though they do have an explanation at the top defining them, and are therefore somewhat confusing about the differences between them.
Terminology is very confusing; for example "link cosmos" is not something most people would understand.
Becoming a member is relatively easy at first, but the final steps and email are confusing.

Advantages

Some blog and some traditional media sources are shown in the results, and this is an interesting view of a search that others did not provide.
Some results from online diaries were included, that others did not include.
The result display is nearly identical to google, down to the formatting and delimeters.

Disadvantages

Does not show keyword in context like Google.
Searches for more than one key word bring up results that are confusing, and often match only one of the words. This did not meet expections as it conflicts with similar types of searching such as those performed on Google which many users are now familiar with.
Searches with know results from other search engines (all those listed above) returned nothing.
Some search results did not contain items from the last week or two, as search engines listed above returned.
Terminology is very confusing: search results can be viewed by date, which is fine, but also by "relevance" and it was unclear from the results what the relevance is based on (authority of the blog, authority of the post? or some other factor). Also, the advanced search uses but doesn not define why someone would search based on an "RSS" feed, or an "OPML" feed.
Joining Feedster gives a user access to various feeds and searches, but the descriptions are not clear about what these are or how beneficial they are for regular users. They appear to appeal only to high level users.