This also assumes that you can have a suitable game within one and a half hours, also that everyone arrives on time and the games can be set up quickly (I don't know what the software limitations are, so I couldn't say).
If you have already started the game, and created your avatar, it takes very little time to enter the HSP lobby and search for a specific table... but for those new to the game, you may want to play around with it before hand, if anything, just to get familiar with the options and controls.
As far as a suitable game length, the nice thing about a casual social game of poker, and not tournament style, is that people can come and go as they like without worrying about how long or short the game might be.
Now if GTP Poker Nights grows in popularity, perhaps we can also have occasional poker tournaments, and in those cases, then we need to have a definite time frame in mind, and escalating blinds to increase the action as chip stacks get larger and players get knocked out. 👍
One thing I want to be sure is possible, is that the lobbies support gameplay across multiple regions, as some game lobbies do not. This should be easy to check, and in fact if anyone in the UK wants to try this out right now I'd be happy to do so.
If it does not support it, the next thing to check is if by logging in with my UK PSN account, or a UK user logging in with a NA PSN account, will we then have access to the same game lobby?
Hopefully, none of that will be necessary, and that all regions have access to the same HSP game lobby, but this should be confirmed by someone before Friday.