Narangz, search engine spiders are very much complex and have grown up a lot
having a /blog or /technology is irrelevant mostly
you might have seen a difference when you had a blank page, first time it might display relevant ad then due to lack of content over time it will goto the public service ads. this first time also just happens for the adsense crawler, google main crawler wont even touch the site without content of traffic
but nothing like that really affects what ads you get when you have content.
search engines can easily recognise even the version of wordpress you are using from the headers. technorati engine even lowers your blog position if you have a old version of wordpress that has security vulnerabilities. even if your blog is named kjsahdklahsd.com but if you have the correct content, adsense always is clearly relevant to the content.
the main reason for the numero uno position of adsense is the relevancy and targetting. which is not so great in YPN (yahoo's adsense equivalent). if your whole site is different (like a company website/portal) and you want to add a blog to it then that /blog theory holds good. but if your whole site is the blog itself, you can perfectly go for having the blog in your root domain itself. no difference it makes. US military forces are censored to all websites which has 'blog' in their url as US military thinks most blogs dont give credible info like news sites. so the whole of blogspot.com took a bit of hit in traffic but blogs on wordpress.com did not
just a small info
and you can check whether and when was your site crawled (or if there is any crawl errors) by adding it to google webmaster central *www.google.com/webmasters/tools/ even specify the www or no www preference in your account.
I also regularly read problogger.net, dailyblogtips.com, smashingmagazine.com they have gr8 tips
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