PCUSA uses Scotts, Heidelberg, Second Helvetic, Westminster Confession and Catechisms, the Confession of 1967, and a Brief Statement of the Reformed Faith
RCA uses Heidelberg, Belgic, Dordt, and Belhar
My impression is that of these Westminster has historically been the most influential within the Presbyterian tradition, and Heidelberg within the continental Reformed tradition. The PCUSA churches I'm familiar with tend to use Heidelberg and the Brief Statement the most.
These churches also use some generic (i.e. non-Reformed, e.g. Apostles creed) confessions as well, but I'm listing only Reformed confessions. Of these, the Confession of 1967, the Brief Statement, and Belhar are recent. C67 and the Brief Statement are specific to the PCUSA. Belhar has broader acceptance. The PCUSA came close to accepting Belhar, but many felt that C67 covered the same issues and others, and did a somewhat better job, although I voted for Belhar simply for reasons of compatibility with other Reformed denominations.
There's been a movement for several years to add Calvin's French Confession to the PCUSA confessions. I find it unfortunate that this document hasn't had more use by Reformed churches.
There are differences in tone and emphasis among the historic confessions. C67 and Belhar deal with more recent issues. The Brief Statement is a modern take on what it means to be Reformed. None of these specifically contradict the historic confessions, though by what it chooses to say and not say the Brief Statement reflects a different understanding of what it means to be Reformed (and possibly even Christian).