The most straightforward way to express your interest in a Jira issue is to vote for it. For organizations or teams that manage their priorities based on popularity, voting is a great mechanism for collecting this information.

An example of this is how Atlassian uses Jira (https://jira.atlassian.com/browse/JRASERVER-9) as a way to let its customers choose and vote for the features they want to be implemented or bugs to be fixed by voting on issues based on their needs. This allows the product management and marketing team to have an insight into market needs and how to best evolve their offerings.

One thing to keep in mind when voting is that you can only vote once per issue. You can vote many times for many different issues, but for any given issue, you have only one vote. This helps prevent a single user from continuously voting on the same issue, which may skew the voting result. You can, however, unvote a vote you have already cast on an issue and vote for it again later; if you choose to do this, it will still only count as one vote.

To vote for an issue, simply click on the Vote for this issue link next to Votes. When you have voted for an issue, the icon will appear as colored. When you have not yet voted for an issue, the icon will appear as grayed out. Note that you cannot vote for issues that you yourself have created.