Would it be considered mean or uncool to force users to update their browsers?

Are you talking about graceful degradation, or are you talking about intentionally serving up an inferior page in an effort to force them to upgrade? Graceful degradation is pretty much standard – pick the browsers you wish to support and then make reasonable accommodations so that older browsers don’t break entirely.

However, you’ll support 99% of users if you just focus on getting Safari 2, Firefox 2 and IE 6 & 7 to work, and frankly the amount of extra effort to get IE6 to function properly isn’t that much if you know the tricks. There really isn’t a need to support IE5, IE5/Mac or any Netscape browser anymore.

Just remember that you don’t need to make them look identical, just reasonably functional. When in doubt:

http://dowebsitesneedtolookexactlythesameineverybrowser.com/

Honestly, as a designer I would love that to happen so that i would not have to come up with hacks for IE6. But forcing a user to update a browser would in the first place take away visitors from a site since most users would be reluctant to upgrade. Simply put, it would be uncool. Its pretty much like web sites trying to installs add-ons to a site.

A better alternative would be to do what facebook does. If a person is using an older browser like IE6, facebook keeps displaying a message on the home page in a special yellow message bar, that they should consider upgrading to modern browser for a better browsing experience

PS. a lot of popular web designers have spoken out on this this issue

If you don’t mind losing some of the dinosaur users, I would totally do it. People still using IE6 need to be pushed along anyway, it’s simply not a secure browser and it doesn’t support the latest standards. Anything that helps push it into retirement is fine with me.

As much as I want my site to be seen by everyone…. I don’t want it to be seen by people who don’t know “update”. To me, they just miss out.

I don’t suppose there’s anything against that – people that use those browsers probably don’t really care about a good experience anyway, since browsers have greatly improved usability-wise.

If it’s worth the effort is another question – I wouldn’t upgrade my browser because some site which wants me to visit tells me to. I just wouldn’t visit the site. Of course, I do update my browser because of all the advantages it brings. Thus, using a deprecated browser already is a degraded experience.

They should make browser expire like beta software. So that you must download a new version of our browser every 6 months or so.

I agree with Vincentt. However, if I’m using IE 7 and I get the degraded experience (which can happen), then I’ll think the site is crap, and no matter how much useful stuff is on there, then I’d just assume not bother to go further than the homepage.

Alternatively, you could just use Push Up The Web