Just a little more info: I've been told that the reason that not all the games have gone over is that MG need to make sure their own product remains significantly different to the licenced product. This means they have tried to find a balance between games that are popular with US players and those more popular elsewhere and do a licensing division with that in mind.
What concerns me is whether this will affect non US players in any way.
Initially, I thought the operators would ditch MGS altogether, and not only US players, but ALL players would find themselves with a new software suite, as happened with Grand Prive.
Now, it seems we won't be affected at all, but the new product is ALREADY so similar to MGS that it isn't going to fool anybody that has ever played at an MGS casino. The fact that merely logging into an existing Viper client will automatically update this to the new software makes this VERY connected to MGS, hardly enough for them to claim this is "arm's length"
There is also the matter of promotions. With the player base split between US and non-US, there will have to be a splitting of promotions, especially of the sort where you wager for prizes. The result will surely be a reduction in the prizes, since the total fund will need to be split between 2 platforms. This might put off players, who will see this as a halving of the value of said promotions.
I see no reason why the new variant cannot introduce it's own multiplayer tournaments in time, this is NOT something exclusive to MGS, and different games & formats would ensure the two products remained different enough.
There might be a problem with licensing the games to online operators AND state lotteries though, since one outlet for the games will be seen as "illegal", and might cause embarrassment for state lotteries offering the SAME games, yet saying they are LEGAL when THEY offer them.
It does mean that MGS have lifted the restriction on operators that didn't allow them to use more than one software, otherwise it would be plainly obvious that BOTH softwares were "Microgaming" if it is claimed the restriction is still in place.
I am surprised MGS went to all this trouble to migrate a player base that only a couple of months ago their CEO said was "no longer commercially viable".
The fact that US players are NOT simply going to be shut out overnight as I predicted is great for them, BUT I am still uneasy about all the contradictory statements, and dark dealings that have been a feature of the last couple of years between MGS, operators, and US players.
I still think MGS have done this because they feared a mass exodus of operators to other brands if they were to simply shut down US players on June 1st, but the timing of this mass migration DOES suggest that this had been the plan all along, to ditch US players by some means on or before June 1st.
Added to this, was the sudden ending of the Red Flush Lara Croft promo for "unforseen circumstances". Well, now it is OBVIOUS, the migration of the US player base to the .net variant would freeze them out of further rounds of the event, and cause much discontent because no US player could win the main prize (there being NO Tomb Raider slot in the US variant, along with the problem of tracking scores across two platforms).
I would expect Red Flush to bring out a split promotion for the summer, maybe brought forward so that US players have an incentive to play with the new software, as well as give non US players something to fill the unexpected vacuum created by the early end of the recent promotion.
It remains to be seen whether non-US players see any difference because of this.
My day would have been in total shambles if I had to go another second not knowing Petros!!!! I happily put my query aside about my very unimportant withdrawal, because now I know Petros!!! 
I would like to say goodbye to all the loyal freeroll blackjack and slot tournament players. It was fun while it lasted and unless the tournaments show up in the USA, I am done with Microgaming. Here is a list of the aliases that will no longer be playing in the worldwide tournaments. 
This is truly heartbreaking as I rarely, if ever, made a deposit.
