Skipping over the usual "3e was t3h suxx0r!" introduction, we get swarms that....aren't really all that different from 3e swarms. They aren't subject to forced movement from normal attacks, which is a change which is really only relevant to 4e. They're vulnerable to area attacks, which makes sense, and is also the way it was in 3e. Instead of automatic damage, they have a free attack on anyone adjacent to/within them, and I'm not sure how that is more "Ah, get 'em off me!" than the 3e auto-damage was. (3e also had them inflict conditions, such as nausea, if you were in a swarm, while in 4e, you only suffer damage. So, again, not sure how the changes meet the stated design goals.)
Looking at the 3e swarm rules, it seems 4e swarms can be flanked, knocked prone (unless that's forced movement), and affected by single-target spells, in ways 3e swarms can't. Melee attacks which do fire damage don't seem more effective against 4e swarms than any other melee attack. So, again, unless I'm missing some special interactions with the rules, I'm not seeing how the 4e swarms are "swarmier" than the 3e ones; if anything, they're more like normal creatures. And I'm not sure why 4e swarms are any less "boring" (my group must have a high tolerance for boredom, as we never thought swarms were any more boring than any other monster; I am beginning to get the impression that the 4e design team uses "boring" to mean "may cause some characters to be more effective than others" -- but this still doesn't work, as strikers and defenders are much less effective against swarms in 4e than controllers and at least some leaders -- the warlord's positioning powers are basically useless.)