Another item that I've seen used a lot which is now deprecated is the :: function calling sequence.
If you have code like:
SELECT * FROM ::fn_virtualfilestats(2,1);
You should now instead be coding it as:
SELECT * FROM sys.fn_virtualfilestats(2,1);
well it sort of makes more sense .. I guess I'd already encountered this but as I can never remember how to call functions in a select I tend to go through the various options until it works!
This makes sense to me if it is a truly a table-value function (like sys.dm_db_index_physical_stats), but if it is a scalar function that replaces a server "function" like @@servername, I see no sense in this. To me this muddles the concept of the original @@servername scalar system functions with the system functions like the dm views (which are sometimes table-valued functions).