After a day of experimenting, this is what I’ve learned: WordPress 2.5 works fine with everything I recommend in my book… except one plugin.

On some (but not all) servers, the Extended WP Contact Form plugin doesn’t work. For me, that’s an important issue.

Are WordPress 2.5’s improvements worthwhile? Not yet.

The new WordPress (2.5) is cleaner to look at and it seems to run a little faster. But–with 20/20 hindsight after a day of testing it–my advice is to install WordPress 2.3.3, and wait at least a couple of weeks.

My sites that haven’t been upgraded to 2.5 are going to stay as they are until late May 2008, at the soonest. By then, the bugs should be worked out of 2.5, as well as the plugins.

If you install WordPress 2.5 anyway…

Nothing terrible will happen if you install WordPress 2.5. Oh, I can’t promise that all of my recommended plugins will work, but that’s the only problem.

The WordPress 2.5 control panels do look a little different than the screenshots in my Sites that Soar! book.

However, the design concepts are the same in both WordPress 2.3.3 and WordPress 2.5. I don’t think that the screenshot differences will cause problems.

When I write a WordPress 2.5 version with new screenshots (probably in June, when the dust has settled with 2.5), my book customers will be able to download a free copy.

Meanwhile, I’m regretting upgrading my larger sites to WordPress 2.5. There are too many headaches with it, especially with important plugins.