Don't install it if you don't need it.
Controls (e.g. pause, volume, stop) often don't work!
Furthermore, you cannot (e.g. by right-clicking Flash content on a Web site) identify the source of unwanted content for the purpose of banning it from your computer. In fact, previous versions of Flash would sometimes but not always identify the source so you could ban an advertising site (or pornography if it ever came up) from your computer by using the HOSTS file, parental control, or whatever. With Flash 10, I have not been able to identify Web sites in this manner.
Best:
Generally plays desired content well. Cannot criticize stability or installation.
Worst:
Full of bugs (pause, stop, and volume control did not work on a Web page with Flash content I just visited) and cannot identify content source for control over which sites are allowed to access your computer. Hence the low usability and functionality ratings. Reflects poorly on Adobe and could affect my decision whether to purchase other Adobe products.
