I have had almost nothing but problems with IE Tab.
A fine example of an add-on (extension) that should never have been written in the first place. If you need to run IE, then run IE - while putting pressure on the site/page/app developer to remove their reliance on IE and/or ActiveX.
What bugs me about many extensions is that they end up suffering the same issues that inspired their creation. There might be enough there to make it compelling, but there's just enough missing to make it complete. Then you have other extensions that offer that missing bit but miss something else. Installing multiple will often result in unwanted duplication and possible conflicts.
Trying to get everything to play nice with themes only further complicates things. I suppose it's always going to be difficult to separate the wheat from the chaff, as they say, when you have as popular a platform as Firefox.
Back onto the Chrome topic for a bit... I think the most unfortunate outcome of Google's entry into the platform space will be the loss of market share for pretty much every other player out there except IE. At least in the shorter term.
The loss might be quite significant given the smaller numbers of some of the players out there. IE still commands at least 70% market share according to most quoted sources, much of that due to use in the workplace/enterprise.
Does anyone know if Google published aggregate browser data from the sites it serves with Analytics? Most of the research companies providing stats have sample sizes ranging in the tens of thousands of sites (40000 for example). Even publishing the agent stats for their own search site would be infinitely more meaningful.