Having seen up to episode 11, I can say one thing with pretty fair certainty:
The opening theme song SUCKS!!!
This Song From Hell is "Delicate ni Sukishite" by Takako Outa, who also does the voice for Creamy Mami and the girl she comes from, Yuu Morisawa.
It is not uncommon to hear it twice in an episode, because--as an idol singer!--Mami's job is to sing.
Now--Takako Outa has a wonderful voice. She's a competent singer, too. But the song--
The end theme isn't any better, but that one's not used as an "insert" song.
An "insert" song is any song which is used, uncut, in an episode, either as the music covering a montage, or when some other music is required. Many series go ahead and use a version of the opening theme, since the production has already bought the rights to it.
The most terrible example of this, I think, comes from the Urusei Yatsura episode "Disco Inferno", in which a montage of the characters dancing in a disco is covered with a synth-flute version of the opening theme, "Lum no Love Song". "Lum no Love Song" is cute and chirpy, and the antithesis of disco music. So while it may have saved some money, the sequence is painful to watch.
This practice, however, has been disappearing, thankfully, since producers discovered that they can cross-license the insert music on extra soundtrack CDs, and make more money. The voice actors like it too, because they are frequently tapped to sing these songs.
As far as the rest of the series is concerned, I have to say that I am still watching it, so it must not be all that bad. It definitely goes nowhere near the top of my list of favorite series; and mainly it's because the story goes for the cheap laughs and doesn't care over-much about logic unless it helps the story.
In the most recent episode I watched (Episode 11, "Papa's a Middle-aged Biker!") Yuu's mother and father have a fight, and he leaves home and joins a biker band (the "Blue Angels", a non-criminal group which is composed of fans of Creamy Mami, of course!). Yuu and her friends can't find the bikers' hangout, so they spread a rumor that Creamy Mami will appear in the town park that afternoon, in the hopes that the bikers will come to see her. These bikers, it is mentioned, are huge Mami fans, and will surely come if they hear she'll be there. (Where have they been at her other appearances? And do they show up in future episodes?? Don't count on it.)
Creamy Mami's manager and the president of the production company she works for--Parthenon Productions--must also come to the show because they haven't been able to get in contact with her; so (hearing the rumor too) they show up in order to discuss business matters with her.
Why, I wonder, haven't they been able to contact her? They haven't been shy about calling her at home! (Something which, by the way, her parents have not remarked upon. If adult men were calling my 10-year-old daughter on a regular basis, I would certainly have something to say about it.) It's not explained why communication has failed in this particular episode; it's necessary that her manager and boss show up at the park in order for a few slapstick moments to ensue. I can't think of any other reason for it.
In Magical Stage Fancy Lala, Lala's manager gave her a cellular telephone, so that--at least--was a solved issue. At the time Creamy Mami was made, cell phones hadn't been invented yet, though, so that was right out.
Also, in Fancy Lala Lala actually had an insert song--"Transparence"--which was actually a pretty nice tune, except for the fact that Reiko Omiori, the actress who does the voice for Fancy Lala, can't actually pronounce the word "transparence", so it comes out sounding like "transbrance". (She has the same problem with "unbalance"; it sounds like "unbrance" or maybe "umbrance", which almost sounds like a real word. Let's see: http://www.dictionary.com says NO, no such word as "umbrance". Nice try, though.)
So, Creamy Mami is slipping in my non-scientific, self-selected poll with a total sample of one person: it's now 2.5 out of 5. But that's still reasonable. And you can't beat the price; I just need to let my computer chew on it for large periods of time--a few hours to download, a few more hours to burn onto DVD. And I do this during times when I'm not using the computer anyway, so it all works out.
Further updates as events warrant.