recently in forum i asked one question whether to change content or not for webpages which are getting rank of 8-9 in SE ranking I did a little experiment and found if you change content even add one picture results will fell from SE ranking. you can read about it here if you want http://www.dwhnow.com/index.php/2009/09/22/my-seo-experiment/ Please mention your points too
Your conclusions are wrong. You should never come to a conclusion based on a single experiment. What happened was normal. New sites rank well for a period of about two weeks, then fall out of the rankings. It can take 6 month to a year to get back. Your site dropped because it is a month old, not because you added an image.
hmm.may be.i didn't change content of another webpage.it is number 2 in rankings and it pretty consistent
in one post i changed text and in one post i put an extra image.both disappeared and were not even in top 100 results.I am not sure about website but for blog(self-hosted) it not good to change content rather create one more post and write some extra stuff in it.it will give better search engine rankings.One of my post which was on rank 5 has climbed to rank 2 now for which i didn't change content
based on my experience, changing content on a page will make google drop your rankings, but only for the meantime, after a few days or a week it will return to higher or lower ranking than before... this is especially true if you change the page title.
Hi Friend, Update is very necessary for your site and content update is very helpful for you because if you will change something in your content then search engine will come on your page then your page will cached by search engine.
I don't think the conclusion you are making is legitimate. What you have seen might have been caused by a bunch of other things. A blog is a dynamic site, it is supposed to change. Changes need to be made - if they make sense to visitors.
did you use alt tags and save the filename of the image as your keyphrase? Logic tells me this doesnt seem the legitmitate cause for your serps dropping.