Geographically, where is your current host? And where are you geographically?
Unless you're moving you or your host to the other side of the ocean, it's unlikely that you'll see improved latency just from changing from one host to another. We've found that the routing from your home computer (or wherever you access DreamHost from) is an overwhelming factor in overseas latency.
You can ping my dreamhost.com to get a rough idea. Or you can use my old server, monster.dreamhost.com.
Free unique IP and $67 off with code [color=#CC0000]LMIP67[/color] or use [color=#CC0000]LM97[/color] for $97 off. Click for more promo code discounts