Allow me to attribute my “reference data” entities, e.g. a Product Catalog, and add support for easily caching the data locally, accessing it while not connected to the internet, and easily incrementally updating it.

Instead of arbitrary improvements that are unrelated to customer demand (according to the content of this forum), pay attention to what people are actually requesting

Have an ability to mark a property on an entity as "deferred load enabled" along with ability to call someEntity.SomeProperty.Load() to explicitely load the property. Primary use is fro BLOB data.

Currently if you create a service operation you have no way to customize the oData fields such as title, author, rights etc. If your business is to sell/license access to data or processing it's a business requirement to be able to brand the data you return. At the moment users who view generated data see blank author fields and inexpressive title fields.

If WCF Data Service has a .NET client, going over .NET Client API, communication between service and that client could be additionaly optimized. I think that this would be very helpfull.

OData is clained extension to Atompub and its main format is of Atom. However, OData does not enforce its feeds(entityset) Atom syndication compliant, and feed readers at large (like google reader) usually cannot render Odata feed properly. Should OData feed be a valid Atom syndication - with Odata extensiton like content/property of course, all feed reader would be able to dispaly it decently, given its content type if atom+xml.

There should be a method that when called, should delete all new data since last SaveChanges (and skip Unchanged entities)
This should include primitive-type props, complex props, navigation-props, relationships (add AND deleted); everything should be undone to original store state.

http://social.msdn.microsoft.com/Forums/en-US/adodotnetdataservices/thread/5fb72704-d424-4495-8736-3a1da11ce75d

Add an option to disable the __metadata as some clients know what they're expecting thus that's not relevant and should not be generated at all!

Now for exposing some entities using WCF DS we need provide
public IQueryable<Entity> Entities in DataContext class, where Entity is class

Be able do the same but using
public IQueryable<IEntity> Entities in
where IEntity is interface
and providing some fabric to WCF DS for constructing instances of objects which implements needed interface

This will significantly increase level of possible decoupling.

This is often a requirement to preserve the order of items in a collection when it's saved and then retrieved. It seems like a basic ORM feature that other systems support (e.g NHibernate) but EF is missing.

This cannot be done in the general case by adding an index property to the collection items, since those objects can be part of other collections, and the same item can be included more than once in the same collection.

Does the EF team consider this feature for a future version? If so how is this going to be implemented?

Title says it all

As far as I am aware currently, WCF data services does not allow users to hide columns.

I recommend that we allow restricted access to columns. Example if table1 has columns C1, C2, C3. and we use WCF Data Services and Entity Data model to expose data in table1 as Odata. I want to allow some users (of my wcf dataservice)to view/access only Columns c1, c2 but not c3.

Currently this is not possible in WCF Data Services i think. Please do email me if i am wrong in my understanding.

When there is some row is added/deleted/modified to the table which is mapped to the Entity, then client should be notified. This would be very powerful feature

Performance boost of using compiled LINQ is tremendous. It would be nice if DataServices would compile-cache query expressions coming to server based on usage statistics. Queries with Skip and Take can be left out for sure but there are always sort of static queries that differ only in query parameters department and caching those would be huge advantage.