Yes! This would be awesome...but this app is powerful enough for you to do this yourself, if you really wanted to. This is basically what I did:

I created a task with each grocery item I buy.
For each task I assigned it to a folder called "Lists.Groceries"
I created all of them with no completion date.

THEN I create a view under "My Views" called "Grocery List", with the following filters:
1. Folder = "Lists.Groceries"
2. Completed tasks

Boom! There's my master list of groceries!

THEN I created another list under "My Lists" called: "Grocery Shopping", with the following filters:
1. Folder = "Lists.Groceries"
2. NOT completed

NOW to use it, I go to my "Grocery Shopping" view under "My View". Everything I DON'T want I mark for completion. Now I have my Grocery Shopping List!

If I want to add something to my Grocery Shopping view, I go to my view called "Grocery List" which has all the completed grocery list items in it. Then anything I want to add to my Grocery Shopping view, I uncheck. That automatically moves it to my view called: "Grocery Shopping". It's really simple!

If you shop at different places for different things, you can also add a context for the location. For example, the things I buy at Costco, I created a context called @Costco. All the items I buy at Costco are assigned the @Costco context. Everything else I buy at Fry's. So if you really wanted to take it to the next level, you could make a View (under My Views" called: Costco with all the items you buy at Costco (Filtered by: Folder = "List.Groceries", Task not completed, Context = @Costco). And have a second grocery shopping view called: "Fry's" and Filter the view by Folder = "Lists.Groceries", Task = not completed and no context (or call it Frys).

IF that doesn't make sense...sorry...lol...but the developers probably follow what I just explained.

Toodledo lists is the one missing feature I'd love to see in UTD!

Absolutely add lists and outlines and habits, too.

This would be a very good addition to your current capabilities. Sooner than later

Toodledo have now released V3 of their API (March 20th 2016) which gives third party apps access to both Lists and Outlines.
Do you have any idea when these will become available in UTD?

Any progress on this? Should we contact Toodledo?

Toodledo has put their version 3.0 API into public beta, which appears to support both Lists and Outlines. More info at http://api.toodledo.com/3/index.php.

Yes, please! Lists in Toodledo are great for tracking things like books and movies that one would like to read or see, but are not tasks. It would be handy to be able to see them on a smartphone when in a library or bookstore.
Thanks for considering this functionality addition.

I would also love to see Lists added to Ultimate To-Do, once the api is available.

Lists is a new feature added by the Toodledo team. Please support this feature in a later update.