I would be curious to the answer to this as well. I do know as knowledge that using Select * on large databases you are going to take a hit on performance.

I tried a test and did it on a small table with seven columns (i disagree that you would list all columns on a table, I wouldn't use a select * but select only the columns I needed)

I did a select * and a select list all columns

This table has a clustered index so when I first ran select * it built the clustered index scan, when I did the select list columns, the results were in milliseconds but the cost from the execution plan was the same Clustered index scan.

I guess the answer is 'depends on what type of indexes are applied to the table/views'????