There seemed to be a marked difference between the old JLPT and the new one. There was a surprising amount of material that was not previously tested on the old 3級. Reading and grammar is fairly difficult to get through in one hour. I sped through the first two sections, skipped to reading, and barely had time to finish section 3. This section requires practice (it's the one with four blanks and you have to pick the word that goes in the blank marked by the star). And I don't know how much pre-written test material there is given this is a new type of question.
Your old 3級 vocab and 漢字 lists are no longer as useful as they used to be. They had a kanji on the test that I have listed as grade 5, 1級. I couldn't believe it. I got this one right by process of elimination. I had never studied this kanji before. They also tested what I consider an obscure definnition (for a beginner) of a relatively common word that was more appropriate for N2 or N1. I also managed to get this one right but that seemed more like a question for a higher level.
The reading passages were quite fun. It's hard to find level appropriate material to read.
聴解 sections 1 and 2 were about as tricky as normal (I had a hard time with this). Sections 3 and 4 are actually easier than before.
I will probably have to take this level again. Wish I could take it in July in the U.S. No one walked out of the room and said the test was easy. THis is in contrast to comments I heard last year (from both people who took 4級 and 3級)。
P.S. The Unicom 3級 books (orange cover) are great prep for N4, especially reading and grammar.