As usual, our friendly answer man is D&D Design Manager Ed Stark.
Q: Will skill descriptions state explicitly whether you can take 10 or 20?
A: We took a page from d20 Modern and Star Wars there, but we broadened our approach. The 3.0 rules already state that you can take 10 on skills only when you're not under duress (unless you have a particular character ability). We've made that more clear and provided better examples. So, you can take 10 when riding down a road (on your Ride check, of course) and the ground suddenly becomes very uneven, but you can't take 10 in those same circumstances with goblins firing crossbows at you. As for taking 20, again the rules pretty specifically state when you can and can't take 20. If there's a skill that has a penalty for failure, you can't take 20, since taking 20 means you'd roll every number, 1-20, in two minutes. Other skills have "you know it or you don't" answers, like Knowledge, and you can't take 20 on them, either. Finally, skills that take longer than 1 round to accomplish don't allow you to take 20 (at least, not usually), as taking 20 takes, well, twenty tries, or two minutes.
Q: What other changes in D&D came about as a result of work on d20 Modern and the Star Wars game?
A: We learned a lot from d20 Modern, the Star Wars RPG, and even material published by other d20 companies. You'll definitely notice some d20 Modern "elements" in 3.5, but you'll see places where we diverged, too. Dungeons & Dragons has its own needs in terms of game mechanics. We won't force things together that just don't fit, but we'll take advantage of evolving rules development as much as possible.
Q: That wasn't very specific. Why are you being so stingy with information?
A: Context, development, and delivery. We don't like to give away "teasers" or bits of information that lead to misinformation. When we put up the pit fiend's stats, for example, it turned into a furor as people tried to extrapolate revision elements from the stats. We were prepared to discuss those elements in more detail -- DR will be featured in an upcoming Dragon Magazine article, for example, and I've answered other questions involving monster stats.
What we don't want is for people to get upset from drawing incorrect conclusions, from reading someone else's incorrect conclusions, or from seeing material from us that isn't fully developed. Let's face it, folks, we're still working on this. If we could release all the information now, we'd do it in the form of three hardcover books, but we aren't done.
Case in point: Many people noticed that the pit fiend stats had no CR rating. Some of them jumped on that to declare that we're scrapping the Challenge Rating system. In fact, we didn't include a CR because we weren't sure yet what the pit fiend's CR should be. Rather than release the wrong number, we left it off. A few people drew the wrong conclusions and stirred up a firestorm of controversy.
We like to learn from our mistakes. As things get finished, we'll release samples for everyone to examine and comment on, and we'll keep the work-in-progress under wraps.
Q: Anything like that you can let us see right now?
A: Well, here's a new feat, Manyshot, along with the sketch of its illustration.
You can fire multiple arrows as a single attack against a nearby target.
Prerequisites: Dex 17, Point Blank Shot, Rapid Shot, base attack bonus +6.
Benefit: As a standard action, you may fire two arrows at a single opponent within 30 feet. Both arrows use the same attack roll (with a -4 penalty) to determine success and deal damage normally (but see Special).
For every five points of base attack bonus you have above +6, you may add one additional arrow to this attack, to a maximum of four arrows at a base attack bonus of +16. However, each arrow after the second adds a cumulative -2 penalty on the attack roll (for a total of -6 on the third arrow and -8 on the fourth).
Damage reduction and other resistances apply separately against each arrow fired.
Special: Regardless of the number of arrows you fire, you apply precision-based damage (such as sneak attack damage) only once. If you score a critical hit, only the first arrow fired deals critical damage; all others deal regular damage.
A fighter may select Manyshot as one of his fighter bonus feats.
A 6th-level ranger who has chosen the archery combat style is treated as having Manyshot even if he does not have the prerequisites for it, but only when he is wearing light or no armor.