Agree, logos decrease the page loading time, and many surfers disable javascript, images and flash objects display. The more fancy, the worst for a surfer wanting fastness not cosmetics, particularly when made using flash, which is censored by CSS authorities like Silktide. I prefer a text logo framed using CSS tricks like groove borders or using 3 layered effect and even surrounded with round boxes made with no images. Not valid for CSS compliance but passing the tests, the use of filters for shadows, glowing and other effects improve the look of such text when surfers use IE 5.5 and above, which is still the predominant browser disregard the claims of Firefox. At least 90% of all the surfers in more than 100 of my websites use IE In side note, if your website needs madly a graphic or flash logo, you can always create it and make an "about us" page to display it, avoiding the main or using a scaled version
i think logo is good for website unique id, if you use the simple text in html is good for search engine..
I think logos are an added decoration for a website. I don't have a logo for two of my websites but logo definitely "spice" up the identity of your site.