I feel unconvinced. This implementation allows gamers to meet up in Home prior to launching - okay, that's a plus versus something like Warhawk where there's no meeting up - but what if your friends are already playing something else, or just not in Home? I'll add a real-world example. A friend of mine plays Warhawk a lot more than I do. If he's online playing and I load up Warhawk, I've no way off getting his attention to switch to a game we can play together in. A couple of times I've created servers named expressly to attract his attention but to no avail.
YES ! These are EXACTLY the sort of real world problems Sony is working on (or needs to work on) at beta. As Nesh pointed out, in-game XMB would be more suitable in that situation. You may not need to use Home at all.
Alternatively, if you designate a regular meeting place, just show up there. When your friend is out of a session, he should magically appear at the same place. The way Home does it is to reify and persist the transient party relationship and virtual meet-ups. So we can manage these temporal "parties" as a concrete user "object". The friendslist is a more permanent and hence, more protected and static, concept in comparison.
I feel that what cross-game party does best is to help two groups of users: (i) The people who's looking for recommendations or something to do (because he's new or bored), and (ii) The regular meetup folks.
In the first case, he'd just ventured into the Home world and hook up randomly by visiting different "rooms". There are additional things to do there to help him make up his mind. We usually talk about Home as if it's a huge unified world, but in reality, there are rooms to set the appropriate context for people to connect.
In the second case, it's just convenience at play. During meetup times, some will be early. Home gives them a good way to explore. The late comers can also wait for an on-going game to finish in Home before joining the party. I don't know if we still need a persistent party leader in this setup (probably yes to simplify the integration initially).
The other questions are:
(1) What happens if the game allows ad hoc connect ? (Probably launch into game from anywhere, anytime using virtual PSP)
(2) What happens if people want to split up and then join later (Should be natural as people leave the room and enter again).
(3) What happens if people just needed a short break while the rest party on for just one session ? (I don't know... leaving the room sounds too "large grained" but it may suffice for a start. Right now, we have to re-invite the player back into the party instead of him just walking into the "real and identifiable" party in Home)
Invites need to be integrated into PS3OS. If we had multitasked cross-game chat we wouldn't need lobbies for that end (though we would to meet up with others not on chat lists of course), but could instead just talk to each other.
"Hi, I'm setting up a Warhawk Server now."
"Okay, let me know when it's running and I'll quit Stardust to join."
"Right, it's done. Look for SUPER_SERVER."
"Okay, I'm there."
Alternatively, just show up at the usual place we meet at Home. This will be more useful when Home is integrated in every PS3 games, and if your gaming social circle grows (like multiple clans or a gaming forum as big as GAF). Your friendslist only has 50 people max. and is usually carefully managed.
A lot of online focus seems to be centred on just playing online, with little regard for who with. The core aspect to any community is creating groups of friends within it and those friends sharing experiences, which means joining up with and sharing with those same friends should be at the centre of the community drive. As it is it's possible for friends to meet up for a video chat, discuss their ideas, and create a game. But only if they happen to be doing nothing other than waiting for a video chat! This doesn't much improve on that. If you meet up in video chat, you can arrange a game. If you meet up in Home, you can arrange a game. That latter is quicker, but no more flexible on the whole. Both require would-be participants to meet up via prior arrangement in a 'meeting-zone' to arrange to play together. I await with pessimistic expectation for Sony to show real cross-game friend functionality.
The cross game party doesn't force you to take a different route. It offers a different way to manage your online relationships and play online games.
EDIT:
How can you make sure you end up in the same "Home" 'world' as your friends?
Have your own clan room, or just knock on his apartment door ("Your place or mine ?")