its hardly more laggy than xbox, and personally i've never had DC issues. if you have however, you need to configure your router and port forward for your PS3, because thats what's causing it. either that or you're trying to connect to other people who dont have their net set up right either, or you both dont have it set up right.
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Slayer_X64
Solo
What Slayer said plus you have to remember that most PS3 users connect via wireless since all PS3 models have a built in wireless adapter. On Xbox you have a higher chance of finding a user who is using a wired connection which = less lag.
Solo
The reason for this is that Xbox 360 didn't come with built in wireless adapter until they made the Xbox slim. The adapter you had to buy before the slim came out costs like $100 at the time.