If you use a "logical" surrogate key in the fact table, for example 20100601, you can still have the time table AND fast searching and simple SQL queries against the fact table. (This method also has its drawbacks, but it works for me)

Furthermore, in some companies, the time table contains much more than just the time, but also holiday information, fiscal information et cetera.

So, I'm not convinced to drop my time tables 🙂