The Shiodome Tower was amazing with the lobby located on the 19th floor it is close to many shopping centers, subway stations, and entertainment venues. When I first stayed we had a problem with the airvents and immediately moved us to a different room, however when they found out we had specifically asked for a non-smoking floor we got moved to a corner suite with a great view. Although we hadn't known our floor allowed smoking they informed us of the mistake and upgraded our room without an increase in price. Breakfast was great and staying in tokyo was a real treat.

This was my second hotel in Tokyo. This hotel is great in every way.
I had a room on 34th floor. I had a great sightseeing of tokyo.
The room had everything even a Personal computer with internet.
I you want to stay in a really good hotel in tokyo than choose this one
or Tokyo park hotel wich is about 30 meters away from this one.

I stayed there for 3 nights in Feb 08. The airport bus to the hotel did not run so frequently, therefore took the Narita Express train to Tokyo Station, then a short taxi ride to the hotel.
Hotel Lobby, restaurant and room were nice. It was a very good business hotel rather than a luxrious hotel. I like the corridor that leading to my room. Room and bathroom were in good size (Japanese standard). Unfortunately the window of my room was facing an office building and one could not open the window blind for any privacy. There was a computer in the room via the television. However, the cable socket for my own laptop was not working and therefore needed to use the computer cable for the TV instead. There was a safe in one of the drawers but that drawer kept sliding opened. Light could be a little brighter in the bathroom.
Breakfast at the western restaurant was pretty nice with good view.
Overall I enjoyed my stay there.

We stayed at the shiodome for 8 nights, the hotels services were FANTASTIC.. the internet in each room is what sold me, i loved being able to see the weather each day and plan our day trips inside the comfort of your own room. Even when we had a problem with the TV, they were quick to react and fixed our problem.
The Shiodome is located in the heart of business Tokyo and walking distance to Ginza, so not too many tourists around here, just ppl travelling to Tokyo on business. The tour companies use it as a pick up hotel, so that has advantedges. However if you want the more Tokyo buzz i suggest staying over in Shibuya, Harajuku or Ropongi.
Another positive is that JR Shimbashi station (for those with JR rail pass), on the main Tokyo loop line is a short walk from the hotel, for non rail pass uses, the Shiodome station is close by, so you can get around easily. Additionally the monorail to Tokyo Bay (Odaiba) is also walking distance.
The negative side to this hotel was the guest services staff, we found that if you weren't dressed in a suit, then they will ignore you to a level of rudeness (ie. prented to make phone calls until you go away) We asked them to see if they could book a tour for us, after saying yes, they never did, and we did it ourselves with our broken Japanese.
The hotel has washing machines and dryers for use, if you do not wish to use laundry services, very handy for those staying some time in Japan.
For the price, I would recommend other hotels than the Shiodome. I only stayed here as I was able to obtain a corporate discount.
BTW, we booked a semi double room, it was more than comfortable for 2 ppl and the bathroom size was decent. I would recommend, to save some Yen, go with the semi double.