Are law review publications helpful for gaining acceptance into a PhD program?
First, I don't agree much with aeismail's assessment that review articles “may carry less weight overall than a traditional research article”. A good review article is very hard to write, because this requires a very high level of understanding of the existing research and literature, as well as strategic thinking to discuss what will be of importance in times to come. To me, this is actually very much harder for a PhD student to have than publishing a “regular” research article. I think most committees would agree.

Now, how will the committee recognized a good review article? Ideally, by reading it and being impressed at the clarity and level of the discussion it displays. In the real world? Probably by the name and prestige of the journal it was published in.

So, my advice is: publish good stuff, in good venues. It matters more that you get to publish things, than what exactly you publish, as long as it is good! (Yeah, that sounds trivial, but you asked for it!)