Let's face it. We all like to check the Google PageRank bar to see how important websites, especially ours, are for Google. This tells us how cool and popular our site is.
So how popular are you? To put it one way, you are as popular as you are frequently indexed. You can easily tell when a page is indexed by looking at the cached copy date. It is not surprising to see pages like digg.com that are always cached with today's date. Digg has a PageRank of 8. You can probably see pages on this blog or yours whose cache date is several days or weeks old. The tricky thing is that you need to consider the update frequency as well.
Here are the steps required to put this to work:
1. Go to the search engine you want to study (Google, Yahoo, Live, etc.).
2. Check popular blogs and news sites that get updated at least daily and check the date of the cache.
3. Repeat step 2 for blogs with decreasing popularity.
4. Create a new post and see how long it takes the search engine to crawl and index your page. If it's not your page, monitor an RSS feed and see when it was cached.
5. Create a table and rank the sites by popularity, include the indexing frequency.
6. Order by indexing frequency and you will have your site rank or importance for that search engine.
While this trick isn't perfect, it does give you a good idea of how important your site is for any search engine. And with a little work, you'll be indexing with the popular kids some day soon!