Of course I was one of the 14 million people that upgraded in the first 24 hours of release. Was that even a question on anyones mind?
Should you upgrade? Well, that’s up to you…Personally I had used the Beta Previews, and any bugs I ran into at the time (for example: iPad connectivity) are now gone and work fine.
But it is subject to bugginess now at launch, and that may scare a lot of casual users away from the product.
Personally I think the pros outweigh the cons at the moment, and that everyone who has the opportunity should jump on the Windows 10 bandwagon.
If you want a good comparison of Windows 7/8 vs. Windows 10, and all the reasons for/against updating, check out this great article from Forbes.