Hmm, haven't heard of this one before. There isn't any chance that you might have accidentally deleted / reinstalled your copy of Pleco in the course of upgrading to the latest version, is there? (did you upgrade on-device or from iTunes?) And this is the Searches, not the Entries tab of history, right? Can you give me a rough idea of what you've done with Pleco (amount of use time, modules / features you've used, etc) between the last time you remember seeing your history fully intact and the first time you realized there were searches missing?
As for the reviews, I think Apple may apply some sort of screening to some of them but I'm not sure why it would take this long to post - are you sure you're not checking the wrong store's reviews? Reviews only show up in one country's iTunes store, generally - we have a program that pulls reviews from every iTunes store, so if you let me know what username you used on your review I can check and tell you whether or not it's posted (and in which store, so that you can then open up that store in iTunes).
To my knowledge, Pleco was neither deleted nor reinstalled. The erasal also happened, I believe, a few days after the update, which was done through iTunes. And yes, it was the searches tab that was affected. Seeing as though I never used the entries tab, I'm unaware of any changes.
As far as what I did with Pleco leading up to the erasal, I basically did it all: using the professional bundle I'd been using the web browser, reader, handwriting tool, all dictionaries. The only products offered which aren't installed are the two German dictionaries. If I had to guess a total amount of time used before use, I'd have to say about 10 to 15 hours.
Anyway, I'm sorry I can't be more descriptive in my feedback. As far as I'm concerned, my reliance on the search history was as sort of a study tool in lieu of the yet-to-be-released flashcard functionality.
As for the reviews, I just noticed that one of 'em posted, albeit a good 4 or 5 days after I sent it.
Thanks for the superior product, dude. You definitely got my word-of-mouth advertising on your side. In fact, I was flipping through my Chinese program's orientation materials and I saw a good two or three paragraphs specifically dedicated to singing Pleco's praises. Word.