According to This article from PC World titled Microsoft May Use 2,000 Developers for Windows 7, says, as the title suggests, that Microsoft will probably have at least 2,000 people working on Windows 7. Now more people are better in some cases, but not in all. Take my FLL team for example. Our first year we had 10 kids on our team, the max amount of team members. That number went down to 8 eventually, and since then our team has consisted of about 6 or 7 team members. We’ve found that the number, around 6 or 7, works best for us. We all contribute skills, and we all have areas where we’re especially good, that’s what makes us a team. Now on a larger scale, I don’t know if 2,000 people is, hypothetically speaking, if Windows 7 is a flop, is going to make a bad operating system any better, hypothetically speaking. But I’ve also learned through my FLL years that more people working on the same thing, programming for example, allows a smaller chance of getting something wrong. So good luck Microsoft.