Search engine inclusion trend experience

Our experience regarding search engine inclusion trend, how search engines are reacting to the new website that are added to the internet world. We'll continue to add our experience as we grow

Website visible in Google Search result using website URLs in 7 days (4-7 days)
Google starts showing Page cache in 20 days
Website visible in Yahoo Search result using website URLs in 1 month (24-30 days)
Website visible in Bing Search result using website URLs in 2 months (50-60 days)
Yahoo includes high importance words in search queries in 2 months

-Sandbox effect* is said to remain in effect from 1 month to 6 month max. in google.
-We are researching if Yahoo and Bing are also having sandbox effect (or like) on websites but as per our experience we were not getting any recognition for our basic keyword included in our domain name.

Our website domain in question was having home page as "Under Construction" for almost 18- 20 months.

After forgeting the website keyword placements for good period of time (without any Onpage SEO and offcourse no OffPage SEO) we noticed that

Bing seems to be giving out most recognition to the On-Page SEO
Google giving out mix response. considering On-Page SEO and ofcourse other attributes that keeps the rank placement shifting (different weigtage to different keywords/keyphrases, etc)
Yahoo probably is looking at factors beyond OnPage and giving them (OffPage SEO) a great importance.