This server-side logic makes it more than just a font-face repository like I initially assumed. If you feel like rolling your own and not using Google's, you can easily download font-face kits from fontsquirrel.com.
A very important advantage is that the browser can cache the stylesheet and the font, and can reuse them across multiple websites.
So if your website uses a font that is used by another website which the user has already visited, the browser doesn't need to download the font again. It doesn't even need to check the modification date on Googles server.
As many fonts add ~100 KB to the download size for a page, this really makes a difference.
Took me one minute to implement. Amazing. The Droid Sans font looks great on headers, using it already. Always wanted to use Typekit but too cheap to pay the costs, this works for me.
I'm glad to see some more of the common pieces of the internet hosted more centrally. There are issues with one company being in control of these things, but we gain a lot of benefits by having standard fonts and libraries available. These benefits include better caching and ease of patching.
Having a centralized structure will help in pushing adoption, but I feel like we should make sure that once we have acceptance, we don't become dependent.
I think I found a bug. That is, a Safari bug that can be worked around by other means. I tried using Cardo (only available as TrueType) on a site I'm building, and it renders inconsistently in Safari (Mac), cutting off lines of type at random heights.
This seems to be a TrueType bug in Safari that can be circumvented by using OpenType or SVG, which I discovered can be easily prepared with this excellent little tool: http://www.fontsquirrel.com/fontface/generator
I ended up opting for my own @font-face linkage with the multiple formats converted by the aforelinked, which seems to render much better across browsers.
Shouldn't be hard for Google to implement something like this, though.
Any thoughts on why Google is doing this other than a perverse will to take over the entire Internet?
My thought is that they're hoping this will encourage more text instead of images as text. That helps them index more information and collect more data on the whole web.
Microsoft (and Apple) did a similar thing back in 1996–7 with "core fonts for the web" in which they tried to push a standard pack of fonts out to everyone so that web designers could assume that end users would have certain key fonts.
Odd, just looking at the compatibility sheet and then my analytics says that Google's Chrome is by far the worst offender in not supporting this. Chrome sits at 15% of my sites traffic and about 75% of that is pre-4.249.4.
Google, usability! I should be able to go from a font page to your really nice configuration page that lets me control it even more: http://code.google.com/webfonts/preview
Dammit Google, why did I have to search my history for a link to this awesome page. Sometimes, I swear people ignore intuitive things that are just too obvious.
Also, I find the use of the word "implement" on this page hilarious. It's dropping the same font-face crap thats been in HTML5 for months into a webpage. The only difference is that it's hosted by Google.
Then again, Twitter was abuzz with everyone freaking out about DnD in html5. Guess if Google's not holding peoples' hands they might as well be useless. I also saw a tweet where someone asked if the REST API would be available for the iPhone. I facepalmed.
This server-side logic makes it more than just a font-face repository like I initially assumed. If you feel like rolling your own and not using Google's, you can easily download font-face kits from fontsquirrel.com.