Spent a total of 4 nights at the Radisson Blu in Addis in Oct/Nov 2012 and will definitely go back to this hotel. Staff is very friendly and helpful, breakfast buffet is a dream, rooms are spacious and well appointed, ATMs are available in lobby (including cash withdrawal on credit card). There is also a bar with creative drinks and a coffee shop. Laundry service is efficient and able to handle sensitive materials.
Best of all: I got to keep my room on checkout day till 6 p.m., without additional charge! Hotel is also well situated for Great Ethiopian Run - just 10 minutes' walk to the start.