Originally Posted by JDR13 
Anytime a sequel is 10 years more recent than its predecessor, it's undoubtably going to be better in some ways. That's a given unless the devs were completely incompetent. That said, I still feel the original Dues Ex was better for its time.
Technically, sure. But in terms of gameplay, the overall feature-set and so forth - I find it's rare to have sequels live up to classics.
I think DE:HR outdid DE in several ways in terms of gameplay. Hacking was quite superior, the basic stealth and cover mechanics were superior - the gunplay was superior. I think the power/upgrade arsenal was superior. The NPC interaction was superior.
The biggest weakness was the boss fight design - and I didn't like the balance of the energy system. Also, the game was overly generous with Praxis points.
As for time of release - I'll admit that Deus Ex was quite ahead of its time, even if it did borrow quite a few gameplay elements from games like Thief and System Shock.
The level design is a wash, in my opinion. DE had bigger levels, but much less visual diversity. Also, I find I appreciate the content density of DE:HR a lot.
But I think we've been through this before. We just appreciate different things.