Well, yes and no. It has it's fair share of quirks, still, but it has evolved a lot since the '90s. Short answer is, it's gotten better. And it's still getting better. I'm told that ECMAScript 6 is going to further improve the language's syntax, and add some features that are sought after. One can only hope that the adoption of ECMAScript 6 will be sufficiently fast.
We've had an increase in speed by several orders of magnitude (not even accounting for Mores law). We have a good set of tools, with more and better tools on the way. we have some amazing looking modern frameworks, such as Meteor. we have unit testing, we have virtually anything you can think of that you'd need to start developing a rich client side application today.
So go download Yeoman (requires Node.js) and start building your client side application today. It comes bundled with Grunt and Bower, so you can take a good look at the multitude of packages already available to you with
% bower search.