I see quite a few posts about Selenium IDE support for IE, etc.
While there’s no such thing and as such record & playback support, just wanted to mention an alternative:
It does require you to know Selenium RC or WebDriver API to make use of. But it also allows a form of record & playback as well.
Read my other posts for background reference:
Using the interpreter shell method, you can try things out in shell (~using Selenium IDE but with RC/WebDriver commands) and when you have what you want, copy & paste to file and clean up to make into a script (Python, Ruby, Perl, PHP) or then compile code (Java, .NET/C#) (~record), and use that output to run commands again (~playback).
This method will work for whatever browser Selenium supports making it sort of an IDE that will work for the non-FF browsers.
And this method also allows you test/verify Selenium locators. You can’t find them using this method (need Firebug, or other tools for IE and other browers) but you can test them using this method to make sure locators work. And you can also run the Firebug and other plugins while using this method so combine those tools with this method and you can find and test locators at same time and know Selenium will work with them, with exception of timing problems that don’t show up under this method (compared to scripts/code).
One other benefit of this method, is it can help you find problems in other browsers like quirks for locators, windows, and other things, if you develop in the other browsers using this method rather than always starting with Firefox.
Besides Selenium Builder, and my interpreter shell method above, there is a new alternative option for a Selenium IDE, see SWD Recorder, read a blog post review of it, or watch the video about it. It’s not an exact replacement but a similar one and is cross browser supported.