I found Ilium very confusing to get my head around, especially at the start.
It wasn't well explained IMO what was going on. Was this a time traveller? What'shis motivations/reasons for going to this time period?
A chapter of character/plot introduction would have been helpful to get me in the mindset. I felt a bit thrown into the story, rather than drawn into it.
I much preferred other Trojan setting books I've read (Vengence of Orion by Ben Bova comes to mind). I haven't read the follow-up book, Olympos.
I get easily put off when authors don't 'start' a story - merely carry on as if you've missed a chapter.
Eriksson gave me similar problems in Gardens of the Moon, and it really puts you off continuing to read the book when you aren't give time to 'settle in' to a story.