As with the battle of the Alamo, Thermopylae is remembered in military history as a delaying action within the context of a larger war. The heorism of the defenders fighting in the face of certain loss for the sake of an eventual victory they won't live to see is the common point between the two battles, though it probably closer to the truth with Thermopylae.
I like the novel for the educational value of its historical context, its depiction of the brutality of ancient warfare, and for its compelling characters. It's also interesting in the larger points it touches on. That is, things that are inherently bad, but that most people seem drawn towards: professional armies, hierarchy, chain-of-command, and "might makes right."
Pressfield is very good at weaving personal stories through the timeline of ancient events, much as Jeff Shaara does with the American Civil War. I highly recommend the book.
If you're a regular reader of my journal, you'll notice that I've revamped my website. I wanted it to be leaner and more to the point of promoting my storytelling, so I pared down the excess. I also wanted to make room for other features like a revamped newsletter and a page for Dentville (my novel-in-the-works).
I have a lot going on right now that makes it hard to be a consistant with these journal entries as I would like. I hope you'll bear with me for better things to come.
You can find my review of Gates of Fire here.