You mean across multiple tasks? If you pull up all the task with that tag, select them all, and hit "m" to turn on multiple editing, you should just be able to edit the tag once and have it apply to all of them.

No, I mean edit the actual tag. For example - I wrote a tag as "wrok" instead of "work". Is there a way to correct the spelling, or to delete the tag altogether?

sheris, there's unfortunately no way to manage tags like this currently, but you could search for all tasks with this tag (by searching for "tag:wrok") and then remove the tags from the tasks (by replacing "wrok" with "work" wherever it occurs). As Aaron suggested, you could use multiple edit mode to quickly edit the tags. Hope this helps!

Thanks, both suggestions worked like a charm.