What do you like best?
I love how flexible the display is. If you add an image to a card, its thumbnail will show up. If you add comments, there will be a comment bubble icon. You can add as much or as little detail as you like, and in card details you can add lists and attachments and all sorts of things. You can also color-code cards for priority or visual grouping.
What do you dislike?
Trello is less good for work assignment scenarios. For example, if you have a larger task that is broken into steps that several different people will have to work on, something like Basecamp will work better for you. However, since cards don't have to be assigned to a single person, scenarios where a single user being assigned being limited make Trello a really good alternative.
Recommendations to others considering the product
Use the free trial to see if it works well for your use case!
What business problems are you solving with the product? What benefits have you realized?
It's easier for me to group my projects by goal. I have a handful of goals each year, and under each of those, I put my overarching tasks. Then I can break down tasks into bite-sized chunks to work on each day or week.