Mozilla may be hopeful for its Firefox 4 release, but it’s hit a bump in the road. The minor delay should push the second beta release back about a week, to this upcoming Thursday. No details on the specifics of the hold up, but Mozilla is still set on its third beta release for August 6th.

Sticking to a frequent update schedule can be tricky, especially for browsers with growing demands. The open-source Firefox browser has a lot of build-up around its 4th generation, and rising competition from others in the space. Last week Google announced that it will also be releasing more frequent updates to its Chrome browser, though their 6-week schedule is still twice as spread out as the 2-3 week timeline to which Firefox is trying to adhere. The Register highlights some of the features Firefox 4 will have, noting what we’ve already seen with the last beta release;

“Earlier this month the first beta of the next iteration of Firefox arrived. Mozilla said it had built so-called “crash protection” into the pre-release version of the surfing tool. It has been working hard to address the browser’s stability, which some users have complained loudly about.

Underlying code in that beta included an HTML5 parser, called WebSockets, that allows developers to create yet more real-time integration for the Web2.0 wasteland, as well as IndexedDB for web apps to use structured storage.”

Another upcoming feature we got a sneak peek at is Firefox tab candy. The improved workflow restructures tabs into organized groups, helping you to keep track of what you’re doing while browsing the web. Last week designer Aza Raskin showed me in detail how the tab candy will work, and, true to his nature, the simplicity of the workflow lies in shortcuts and visually strong navigation around the schematics of browser behavior.

While Firefox 4 looks to the future of web browsing, the stability and security of current web browsers remains an important topic. A security update for Firefox was just released to address plug-in issues found in the recently launched version of 3.6.7. Microsoft’s Internt Explorer also got a boost this week, announcing that its SmartScreen Filter has stopped 1 billion pieces of malware from being downloaded.

Here’s some tab candy to check out:

An Introduction to Firefox’s Tab Candy from Aza Raskin on Vimeo.