It's entirely up to you. Personally, I am happy to let others find the snags, and will wait a while until they are ironed out. Even then, I will make a new mirror image in Acronis before installing it.
You will see from other threads re IE8 that some of us have had no problems at all, others have had a load of hassle and will not use it. It's a personal decision so try it and see but also no harm waiting a while to see how/if/when Microsoft release patches for it.
I myself had no problem installing or for that matter uninstalling it,although my installation did take a fair time after reboot before arriving at the desktop, displaying a black screen and a small box at the top left informing me of personal settings or similar being made. I had a few small issues that made me uninstall it, perhaps more to do with add on programs than IE8 itself. I also have an acronis backup in place if things go wrong which allows for trying programs out without having to endure a lengthly reinstallation of Vista, updates and programs.
I'm not saying that you'll have problems but others have had installation and worse happen, If you can wait a while it might be best, if not and you have a backup plan in place then try it today.
and although I've had a couple of glitches I believe it hasn't been IE 8's fault. I installed the beta of Windows 7 on the same machine, and immediately I ran into a problem with IE8 - it wouldn't allow me to paste a url into the address bar, it just crashed every time.
Now that IE8 has been released for general use I can't install it - I get a message that the software isn't compatible with my operating system.
It looks as if Microsoft has backed me into a blind alley. I can't uninstall IE8 beta, and I can't install the new release until Windows 7 launches in its final form.
It took about 3 minutes or so I guess, I thought it had crashed myself but I've learned over the years to leave things for a while before presuming the worst.
Microsoft need to provide a progress meter or similar in situations like this, if I remember rightly updating my old desktop and notebook to XP SP3 also had a long delay during the process giving the impression of a crash. The drive light didn't go out on these occasions though which is always a good indicator the program is still working.
Left mine longer than that. You know it's doom and gloom when the HDD light goes out and stays out. Task manager would open but wouldn't respond and CTR ALT DEL brought the options up, log off shutdown etc but nothinging responded. Tried installing twice... wait now and see what MS say, submitted a request. I'm not reinstalling Vista though ! Thanks