Many months ago I posted a widget wish list request to my blog. The response was overwhelming. I'm sorry I haven't gotten a chance to respond to that thread (until now). I did read all the responses, and won't be able to address all of them, but let me respond to a few.

Added features:

Since the 0.9 release, we've added a number of frequently requested features to dijit and dojox:

Documentation - thanks especially to Craig, Neil, and Peter we now have both The Dojo Book and the Dojo API reference

Lazy load editable table: dojox.grid (thanks Scott and Steve!)

Charting: dojox.charting (thanks Eugene!)

More tree features: dynamic updates, DnD, icons, etc. The tree now has DnD, and also will update itself dynamically according to updates to the data store. However, this is still a work in progress. There's an issue with ItemFileWriteStore in that it doesn't maintain referential integrity: you can delete a child without deleting the reference to it. And also, the dojo.data API doesn't support lazy-load of specified attributes, which means that an item (representing a node in the tree) must contain at the least a list of the id's of it's children, which is not a good model for lazy-load of tree children. Many people have also requested the ability to directly control the contents of the tree rather than going through dojo.data but we've resisted that as we want to keep dijit simple.

File upload: dojox.widget.FileInput (thanks phiggins!)

A server-proxy dojo.data store: dojox.data.QueryReadStore (thanks Wolfram!). Many people have been confused and think that FilteringSelect/ComboBox need to download all the data to the client, but that's not true. Rather, that's just a property of the dojo.data provider. The provider can download all the data and filter on the client (how ItemFileReadStore works), or it can pass every query to the server (how QueryReadStore works), or somewhere in between.

Drag and drop, reordable lists: dojo.dnd (thanks Eugene!) This is not a widget per se but peole tend to think it is, so I've listed it here.

form widget width setting - Can now set the outer width on input type form widgets (*TextBox, FilteringSelect), and that width includes both the size of the down arrow and the input typing area. Makes it easy to make all your fields the same width. But not supported for buttons yet.

Still on the list:

Now here are some frequently requested things that we haven't implemented [yet]:

Support layout widgets inside hidden components like dialogs - I often see (duplicate) bugs about how TabContainer or other layout widgets don't work when placed inside a Dialog, or are otherwise hidden during instantiation. This is definitely an issue, but is hard to fix, since widgets that do javascript sizing can't initialize when hidden because their computed style (like the computed height) turns up as 0 or NaN. And even when using the "A List Apart" 4-corners technique we still need to use javascript to compute the height of the tab labels, which varies depending on the browser's font setting. That's still an open issue.

Control positioning of tooltips/ValidationTextBox tooltips/tooltip dialogs - many people have asked to control the positioning of tooltips (including the validation error tooltip messages), so we'll have to do that for 1.1. The obvious position to put a tooltip is below the target object, but the problem is that it covers up the drop down (from a drop down button, FilteringSelect, etc.). Suggestions welcome.

Documentation about how to style a widget (IE, the CSS attributes) - I'd like to get this done eventually although obviously it's a very big job. Volunteers welcome.

MenuBar - We have a ToolBar widget that's quite similar to a MenuBar widget, but there are subtle differences like the ability for a menu to open just by hovering, without clicking. People want a MenuBar that mimics Menu exactly (except that it's horizontal instead of vertical). Planned for 1.1.

TabContainer/StackContainer with flexible height - this is the doLayout=false flag for those widgets and we plan to support it in the 1.1 release, at least for StackContainer, and for TabContainer where the tabs are on top. I'm not sure about other TabContainer configurations though, like having the labels on the right. Would be interesting to hear what people need.

LayoutContainer with flexible height/width, or with no height adjustment at all - I see these requests fairly often but I haven't been convinced that a widget would add much value over just using a table, so no current plans to implement this feature.

Non-modal Dialog - People often ask for dijit.Dialog to have a non-modal option, although actually you can already do this with dojox.widget.FloatingPane. But perhaps we should roll that functionality into dijit. For me the substantive difference between Dialog and FloatingPane is that Dialog sizes itself according to it's content, whereas FloatingPane takes a predefined size (and has a scrollbar). People also often ask to specify a height, width, or maximum width of Dialogs, the first two of which are easily done by making the dialog contain a <div> with a predefined width/height. minimum-width is more difficult but can be achieved using CSS and expressions.

Other things:

There were many more responses about widgets people wanted. We'll never be able to implement all of those requests but my advice is to try submitting the widget yourself. There's always lots of help for aspiring widget writes on IRC, and we always welcome new submissions.