For online play, generally shorter "30-60sec" maps are more desirable. The reason being... you can do many more runs in the given timelimit and improve your time quicker. It's also nice that if you mess up or crash, you've only lost about 30secs instead of wasting 5mins on a wasted run. Some people just can't drive for 5mins without messing up.
These shorter tracks have always been most popular online in TM, and that probably won't change in the foreseeable future. So many authors build tracks within that timelimit because they wish to see their tracks played online.
Even for offline play, about a 1min to 1min 30secs is about the threshold to which most people want to sit down and hunt a good time on a track.
There
are people who enjoy longer tracks though. Let's look at some examples:
- Over
40 people built tracks over 3mins long for the Monthly Track Contest on TMX United in March-April 2010.
- "
Size Matters Even More Now!" and "
does size still matter?", two Desert tracks by tmjonas (both over 10mins long) received over 20 awards each, the latter receiving over 40. And both of these tracks have been played numerous times online.
- "
20:01 a coast odyssey", an amazing Coast track over 15mins long that took 2 years to build, received over 35 awards and some of the top Coast drivers hunted times on it. It was also played on numerous occasions online in time attack mode with the timelimit turned off.
- The "
mx Crew on Canyon 1" track has received 58 awards and 25 replays uploaded. The top 4 replays are all within half a second of each other. And this track is just over 3mins long.
- Lastly, the CMC (
Coppers Millions Cup) is a competition on endurance tracks held in United. It has seen many editions and dozens and dozens of tracks have been specially built for this contest. It has now come to TM2 in the form of the PMC (
Planets Millions Cup). I'm sure they would welcome some track submissions if you enjoy building long tracks.