Probably because Music Island is listed on the "Showcase" Tab of the Second Life search engine, newcomers show up at the venue hourly and are disappointed to find the venue empty and quiet on days when no programming is scheduled. If I happen to be there and chat to them I sometimes hear their frustration at wandering Second Life for days on end and finding only empty places. Although at any one time there may by 60,000 of the millions of Second Life citizens logged on, the virtual world is huge and it is a mistake to wander aimlessly if you wish to find people and events.
While Second Life is a 3-dimensional world with a lot to see in the various builds, it is still organized very much like the rest of the social web. You learn about events of interest through who you know and which groups you choose to join.
So if you are new to Second Life, wonder where all the people are or are finding it difficult to find events that interest you there are a couple of things to do.
First search on "Events" in the Search Engine and then then from the drop down menu further look for "Live Music", Arts & Culture, Education, or whatever broad category you are interested in. Click the "Search" button and a list of events will appear. Remember that the listed times will all be in Second Life Time (Pacific Time) which you will find in the upper corner of your viewer. (Please don't be cranky about things not being listed in your own time zone. It's a big world and most of us have to think in many time zones all the time in our jobs ... people who fuss about needing to convert to Second Life time are quite annoying.) Once you find something you are interested in you can click on it, get the details and a landmark to go to the event when it is scheduled to beging. Getting to popular events early is a good way to avoid disappointment as events do fill up.
Not all events are listed on the Second Life event listing. Most are promoted only to interest groups. So next go to the "group" tab on the search engine and type in some search terms that correspond to your interest. Try joining some of the open groups with a large membership that look interesting to you. Once you have joined I suggest you go into "group info" tab in the group window. You will see a list of the notices for the past month. If there are no notices then you might want to quit that group and join another. If a group is not sending any notices of events in a whole month, it's dead or pretty slow. If you see 4 or more notices, it is lively. Open the most recent notices to see if there is an upcoming event to go to. You will soon start to receive notices from the groups you have joined inviting you to events of interest. There you will meet friends and likely be led to other groups that might be an even better fit for your interests.
When you meet an avatar with similar interests to your own, click on their profile and see what groups they are members of and what venues they have in the "Picks" tab. There is no way better to find great groups than to see what groups other people who share your interests have chosen to join.
Expect to join and quit groups quite often in your first months in Second Life until you find a good mix that brings you news of things that interest you. Following these strategies, the only time you will be alone on Second Life is when you choose to be alone. Exploring new places is fun too!