It is still in Beta testing and it has very limited functionality, but timetrial.in is live for beta testers (everybody running in our first Time Trial event on Wednesday.) Our team of developers is working hard to make it better and easier for runners at this point. And we have quite a few surprises in store, so keep coming back.
I believe that there is a lot of emphasis on running further and further currently. I am one of those who loves running for the whole day. BUT, we do not always have the time for it and we do not get the heart rate sufficiently up to get the most benefit from running. Time Trials helps with this and is a great way to get a good workout that makes you faster. A fast 5k once a week is good for building speed.
One can talk a lot about the percentage of running that should be done at which heart rate to be optimal, but I will leave that to the coaches. My personal experience is that my times for all the distances started improving when I inserted once-a-week speed/strength training into my exercise program. I have been running for 15 years, but during the last 2 years, I have improved my personal best times for most distances including the 5k and the marathon. I ascribe this to grace from God and my regular speed workouts.