How safe is my computer if I get on facebook regularly?

[Ilovemycountry]

Sometimes when on facebook I get redirected to a website for McAfee site adviser. Telling me the web-page has been tested and had some issues with browser security compromise or something like that. In the comments someone said it is the advertisements on facebook causing that. Can anyone give me additional info on this? If you answer please tell me your experiences with "facebook".
Flybishop , I like your answer the best so far but would like some supporting documentation or how you know that. Do you have experience/training in computer security?

[David M]

Some of the apps on Facebook can freeze up but i don't think it will destroy your computer. It is best to get some kind of safety system tho.

[JKHILL07]

It's most likely the banner ads are a bit dodgy and McAfee is picking that up, as long as you don't click on them you'll be fine =D

[flybishop]

Sometimes when you're on facebook you're not really on facebook. Like if you're using an application hat you installed some of those applications are iframes which are displaying content from other sites. Sometimes you don't know who that site is or if they can be trusted. Furthermore, just by installing that application you are allowing that person access to a lot of your personal information. The ads probably won't do it because they have more control over them, but question which apps you use and whether it's just fluff or you really like it and use it a lot.

For instance I can write an app that is hosted on my website, which could be a known problem to McAfee, and in my app I could write it so that it sends your personal data, and who all of your friends are, to my server and store it in my database, and even if you delete your facebook account, I've still got it.

Facebook itself is safe, but some of the apps may be suspect.

[Smith]

If you have a good antivirus software so it doesn't matter whether you use it whole day or for one or two hours.