I am going to answer this, only because I already know the answer... I have been following this topic on the French board for a while now, looking for info myself.  If a mod wants to look into this topic and provide confirmation or additional clarification, I'm sure everyone would be interested!

The current OhMyGames collection was introduced on June 15... it should have been replaced on August 15.  I would love to provide a link to the thread validating that date, but it has been removed (unless I somehow missed it... feel free to post it if you can).

Upon failing to find the introductory post on our forum, I went to the French forum where it was still available.  From the discussion in their thread, I learned that the current collection would remain in place for an undetermined length of time... the OhMyBoutique prizes would not be changing on schedule.  Again, I would love to provide the link to THAT thread... but it has since been deleted (unless, again, someone else can find it and post it... but I have looked carefully, both here and there).

Despite Sarah's reply that the current collection would remain in place for an unknown amount of time, players continued to post questions about WHEN the new collection would arrive.  These questions were directed back to her original reply:  Unknown.  Eventually, that thread was locked for redundancy... and now it is gone.

Other threads addressing the same topic have been locked... so the (unofficial) answer is "I don't know".  Given that there has been no additional information forthcoming from Sarah, and related topics have been locked or removed... I can only suggest that we be patient (very, VERY patient :P).  I, too, am most anxious to see a new collection, and would even be happy with an update...  I'm sure there is a good reason for the delay!

The French topic DID say that a countdown timer WOULD be put in place, and a News post would be added BEFORE the current collection retired and the new collection arrived.  Again, can't substantiate this info with a link... but perhaps a mod can ^.^

I do know the answer to this:

iklovech wrote:
How long have those items now?

4 months and 5 days (and counting :P)

I don't buying tokens. Right now I can't. I think why peole aren't buying tokens cause there is people who have gotten the casino room. I bought a lot of tokens for that.

New item will be really nice for once.