I first got into them back in either '03 or '04 after hearing Requiem off Ember to Inferno. I loved it because it was very thrash oriented and I wasn't listening to many bands that were doing the scream/sing thing. Also taking into account Matt Heafy was only 17 when he wrote the songs for ETI, I thought it was pretty damn impressive. Very shortly after that I found out they were coming to town to open for Iced Earth so I went and checked them out. I saw Matt hanging out before the show and appraoched him to tell him that I liked his music and he gave me a perplexed look and said "You know who we are?!" There couldn't have been more than 15 people paying attention to them while they were playing. It's funny to to think back on now.
As far as Ascendancy goes I like it a lot and still do, but as more time passes I prefer Ember to Inferno. Like I said, more thrash influenced and raw sounding. What's happening now is you're starting to see all the backlash from the hype they've been getting and over-saturation in the marketplace of bands that are all using the same formula. If you were to play Ember to Inferno for people who hate Trivium a few years ago they would probably love it. Their next album is going to be very pivotal for them. From interviews I've read it sounds like they want to silence all their critics and I think they can do it.
Here's an early clip of them if you want to see how they were before they broke:
http://youtube.com/watch?v=-vhxrFu-nAs
And my pic: