In limited testing, it misses a threat
Although I did not put the software through full laboratory testing, I did test it using the EICAR Standard Anti-Virus Test File, which was developed by the European Institute for Computer Antivirus Research as a way to allow antivirus software to be tested. The test file acts like a virus, even though it does no harm to your system.
I tested NIS 2010 using two versions of the EICAR file: a .com file (a type of executable file), and a .com file embedded in a zip file. Norton said that the .com file might be dangerous. However, it allowed the .zip file through without any notice.
Note that these were only two test files and NIS 2010 is still in beta, so this is not a true test of how much protection the software will give when it is released.
Other new stuff
Besides Norton's new reputation-based security strategy, there are some new features. One is what Symantec calls "Autopsy," which gives more information about threats on your system than previous versions.
The anti-spam component has a new engine from Brightmail, which powers many large enterprises' anti-spam efforts. Symantec claims that this significantly increases the efficiency of its spam killing.
In addition, Norton Internet Security 2010 users get a free subscription to OnlineFamily.Norton, a Web-based service that lets parents control what their kids do on the Web. However, that subscription offer is good only from when the product is released until December 2009.
There are other minor changes as well, not all of them good. For example, there is a new Vulnerability Protection link on the main screen, but the link just takes you to another screen that doesn't appear to do anything -- at least, not in this beta. It merely lists programs that Norton has found to have vulnerabilities and which you are protected against, whether or not you have those applications on your PC. It feels like a bit of marketing thrown into the middle of the program.
Conclusions
So should you download this beta version of Norton Internet Security 2010? Given its installation bugginess -- and the fact that it appears that the subscription may last only 14 days -- the answer is most likely no. And since it uninstalls whatever security program is already running, you certainly won't want to put it on your primary computer. The software is set to be final sometime in the fall; you'd do well to wait until then.