Although this application supplies a bit of needed user-friendliness, there are some disappointing restrictions buyers should be made aware of.
First off, the setting for SSID is misleading, as the application supplies it's own prefix for the name. For example, if you decide to call your hotspot MobSpot, the SSID that is visible is Joikuspot_MobSpot. I find this completely unnecessary, and can only be viewed as an attempt to force advertising, which I don't consider ethical as customers have purchased the full product and shouldn't be subject to this.
Another weakness is the choice of channel (which they dub frequency for some reason). The only choices are 1, 6, 11 and Automatic. There is no reason for Joiku to not supply the complete scale of available channels (restricted by country, of course). I live in Norway and would normally choose 9 or 13 to avoid overlap with the commonly used channels, which is known to degrade performance significantly.
I have also noticed that my connection from my laptop seems to bounce between 1 and 5.5 Mbps connections. This may not be a problem with the application, so I will keep criticism to a minimum and just say that this is unfortunate. I don't have speed issues from my N900 using WiFi and don't understand why this is an issue using JoikuSpot. This may be a consequence of the channel restriction, but I haven't had the possibility to test this out.
The application is ok, and for those that require a user-friendly way to supply wifi-tethering this is a must have. There is a free alternative now, Mobile HotSpot, which can be found in maemo.org's repositories, but this is said to not supply the same functionality. I will be checking it out shortly to compare these two for my own sake, and will post my opinion here just in case someone wants to check it out.
UPDATE: JoikuSpot doesn't actually work as an access point, but creates an ad-hoc network. :|
UPDATE2: After more use of Joikuspot, the speed was improved from when I originally tested it.