I've finished Half-Life 2 Episode 1. It was more of the same Half-Life 2 style gaming. Not that it's a bad thing, as the Half-Life 2 standard is still high calibre entertainment, but most fan responses I've read was that they expected a little more (in addition to its length). And I've also finished the episode 1 commentaries, or perhaps more aptly named "How to make a good (FPS) game 101". It was very enlightening to listen to the comments and thoughts of the Valve development team, of what worked and what didn't, of problems and solutions, of inspirations and ideas. Other developers would be wise to take heed and benefit of its insights. For example, initially, Alyx would on her own will give away what do to next, but they noticed the playtesters were unsatisfied with the accomplishments when the steps were blatantly revealed/forced upon them. So they sealed Alyx' dialogue, and she basically becomes a "hint-dispenser", and would only give hints if the player asks for it from her.
With regards to the episodic content delivery, I for one welcome it. $20 for ~5 hours of entertainment (it took me 6 hours to finish it on hard difficulty, a bit longer on commentary-mode), it equates to $60 for ~15 hours of fun, which is the price of a full game. Considering some full games offer less duration than that (~10 hours), it is not such a bad deal. Plus episodic content enables developers to deliver bite-sized chunks of gaming in less in-between development time. Instead of waiting three (or more) years for a full game, the full game can be broken into three portions, released once per year. This way, the consumer waits less for new content. This also puts less pressure on the developers. Frankly, I think it's a win-win situation for both the developers and the consumers, and I can see more game series taking this route in the future, such as SiN:Episodes, which I also purchased.
As for Half-Life 2 Episode 2, I've read the article, and it appears it will be more expansive than Episode 1. There will be more greenery and scenery. Gordon will travel as much space as he did in Half-Life 2, and yet within the span of the 4-6 hours of an episode. This implies Mr. Freeman will be moving quite a lot, no doubt aided by the new vehicle. And for better or for worse, if you like Alyx or not, there will be less of her in episode 2, which means she will not be with you all the time, considering she was pretty much by your side every minute of the way in the first episode. I look keenly forward to it, as always for the Half-Life franchise.
I've took the liberty of scanning the Episode 2 article preview from the August 2006 PCGamer issue. The scans are quite large, so I'll just link to the
folder.