Helsinki is using the convention center, which has an attached hotel, a bunch of small to medium sized meeting rooms, way too much exhibit space, and a couple of nice large auditoriums suitable for the Hugos.
Like most hotels in Europe, the hotel attached to the Helsinki CC is too small -- only 244 rooms. We do have the whole thing, which is nice, at reasonable rates, and as in Glasgow it is an easy transit ride to a lot more hotel rooms. Unlike in Glasgow the transit will be free.
The meeting rooms are on three levels, which is good as it cuts down on walking, and they're a mix: some rooms that split up (which is handy) and some that don't (which makes for better sound isolation), some that are right on a central foyer and some that are more hidden, some little ones and some big ones. The entrance to the hotel is also right on the foyer rather than off to one side, which means those rooms are right there. The particular sizes of the rooms are an unusually good fit for a SF convention. The arrangement of rooms and the different sizes available mean this is true for conventions ranging from 2000 attendees up to 5000. The airwall vs non-airwall room configurations (and resulting room sizes) are similar to those of the Westin Waterfront in Boston, which is happily home to both 1200-person Boskones and 3800-person Arisias, without either con finding the space terribly inappropriate.
Behind the meeting rooms are some big exhibit halls. Too big, as usual, but the convention center will rent us any fraction of one we like and charge us only for what we use. Unlike many other convention centers the exhibit halls are *not* stacked with the program rooms, so the exhibits aren't isolated from the rest of the convention. A convention with a lot of exhibits would entail a lot of walking in this convention center but because we'd only use a little bit of exhibit space, we won't have that problem.
One thing you will often hear me complaining about is the unsuitability of many facilities for hosting the Hugos. These days 60% of the attendees go to the Hugo ceremony so you need a great big room. But the Hugos are the only thing that fills the room, and it takes a long time to set up and tear down and rehearse for, so many Worldcons wind up with a big dark spot in the middle of the convention that everyone has to walk past to get from one program room to another. The room itself is expensive and mostly a wasted resource even or perhaps even especially if you put the Masquerade in there too. Helsinki addresses this in several ways. Unusually, we only pay for the nights we're actually using the room. Also unusually, although we pay for tech from the CC, we *don't* pay for the time it takes to set up and tear down the tech, which means we save money compared to some fan-run tech setups. There are two possible rooms, both located where their darkness will go unnoticed during the rest of the con, and if the con is big enough to need the larger one for the Hugos but the smaller one still fits the Masquerade we can do that without paying extra.
Convention centers are expensive and this one is no exception. The fact that we only pay for the space we use means that the facilities cost per attendee is much more predictable even though we don't know how big the convention will be. I put together a spreadsheet and it looks like the cost of function space and tech comes out to between $80 and $90 per member, which is a little on the high side for a Worldcon but not completely off the scale. What's unusual is that this number holds whether the con is 2000 people or 5000. Above 5500 or so things stop fitting so neatly (as they would in the Westin Waterfront, too) and it gets more expensive to fit the con in to the space. It's hard to imagine that Helsinki could really be bigger than Noreascon 4. If it is, though, there are probably enough other amortized fixed expenses that we can afford to spend $100 per member on space instead of $85.