Almost through Week 1, and I am both encouraged and discouraged. Day 1 - try as I might, I could only do about half of the workout. Not that I gave up, but I honestly couldn't do more than a few pullups, zero DiveBombers, and only a few Diamond and Wide pushups. Day 2 - Plyometrics SUCKS, but was able to do it all with some breaks. Same with Day 3. Ab Ripper X was pathetic on Day 1, improved on Day 3, we shall see today if I can finish. So I am encouraged that I feel like I'm working hard, but is anyone else finding that there are a number of excercises that they cannnot even do a single rep of? I have tried to similate the pushups and pullups that I could not do on a BowFlex, and I expect that by the end of the 90 days I'll be getting them, but wondering if I should go back and do a round of P90 first.
Any feedback on this decision would be appreciated, especially by those who are further along or have completed a cycle of P90x already.

Yea man, I was in exactly the same boat as you when I started. I didn't give up on day 1, but when you can't even do a single push up and your half way through, your pretty much done. However, the next week I finished the whole workout strong (first time i couldn't do a diamond push up when it came around, second time I was busting out 10) And trust me man, it feels awesome when your done!! As long as you worked your tail off all week the next week will feel a lot better.

Don't get discouraged man, you don't need to go to p90. Take it from someone who had the exact same results as you, it gets better!

Thanks. I assumed I was in familiar territory here. But I just needed to hear it from someone else. I AM working hard, and have had an easiER time with Arms/Shoulders, etc. It is frustrating, as up to when I started grad school I had always worked out regularly. So to not be able to do half of the first few workouts was embarrasing. Like I said, I'm sure I'll be knocking them out by the end, but just wanted to make sure I was making the best use of my time until then.

Keep on trucking, you will be suprised at what you can do week by week. I had a hard time with some stuff too, but I kept at it and now I can keep up with the big dogs!