15 seconds to load a page. Please help out

[pmeenan]

I don't think that would be related to the W3TC issues but my guess is the old and new sites are referencing the same database (or a copy of the old database) and something in there is still configured with the old URLs. Do you have redirects in place to redirect all of the old content to the new domain?

Did you dump the database from the old site and load it into the new database or are you trying to point to a new database (that won't be pretty)?