I've noticed alot of sites appearing on the first page for web design on the UK google using IE hacks in their scripts. Is it not better to just develop the site correctly to work cross browser without these 'hacks'? Or does google prefer these as it actually says it is cross browser compatible in the script.
To test what works best with Google, you need to see your website in a text browser like Lynx. That's what Google advises. As for these IE hacks, could you be more specific and give examples of what you are referring to.
I can't imagine that using IE hacks has any effect on your SERP.... I can almost guarantee that it doesn't.
IE hacks won't affect your search engine rankings. But I do agree with you though - people should learn how to develop Web sites properly.