Sound
The sound in the new frontiers far surpasses that of the old frontiers, including the sounds of large battle around the keeps. You can hear blades clashing, soldiers screaming, bows being drawn and fired, the roaring of a wizard's fireball. I've found that when wearing headphones you can even hear things behind you, or off to the side. This combined with appropriate ambient musical scores for the various areas of the frontiers provides for an air of excitement to the game, however, just like with any other game, after a long period of listening to the same looped sounds over and over again, I find myself switching to my MP3 collection for variety and change.
Value
Though the new frontiers took much away from the small scale battles that use to take place with the implementation of much easier travel methods, the keep battles are still much fun, and players have branched off a bit to seek smaller battles when they can. This expansion would probably be worth paying a modest fee for...but since it was completely free to the player base, you just can't beat the price, heh.
Fun
The excitement of watching your catapult blast a hole in a keep wall, or your warriors crashing a battering ram though the keep door makes for a fun action packed experience. However, new frontiers rapidly became a game of ranged warfare, and with the decline of open field battles, the melee classes soon found themselves twiddling their thumbs or being shield guard for a caster in the majority of the battles that took place. While this free expansion undoubtedly improved keep warfare, it may have put a bit too much focus on the keep warfare, which in the end took some of the feel and the fun away from the game itself. With the easy teleportation from keep to keep, the need and circumstances for open field battle all but disappeared.
Community
With the aging of the game, and the higher numbers of elite veterans, a new player may find it difficult to find groups for PVP unless they fit strict criteria that certain groups are looking for, however, if you can find a decent guild, there are plenty of nice people around willing to help you out, and show you the ropes, you just may have to look a bit harder than you would in some newer games, being as there aren't as many low level people running about.
Performance/Lag
In most cases, lag is almost non existent compared to many games that are out now, many times if you are experiencing lag it is from your computers end of the spectrum, and you can tone down the graphics, etc to compensate and improve performance, however, with some very large scale battles, where you have upwards of 300 people in a relic raid or some such, you will sometimes encounter crippling frame freezing lag.
Customer Service
Customer support through email for technical difficulties is very thorough and helpful, however, in game support leaves much to be desired. The waits in game are often hours long only to have the customer service representative tell you that they can do nothing for you. At times they can be helpful, and in game help menu provides a good bit of information for you to work through before calling on a CSR. One thing mythic is getting very good at are spotting hacks and exploits, and quickly putting them to a stop. There will always be hacks and exploits in any game, new ones are created as fast as old ones are stopped, but mythic is putting forth a good effort to keep cheats to a minimum.
I have to say kudos to the mythic team overall with most of their expansions and continued success of Dark Age of Camelot. With many new titles pending in the next year or two, Mythic has their work cut out for them if they want to keep DAOC near the top of the MMO list, but so far they have done a commendable job running a solid game, which only gets better over time with constant patches and updates.
Role-Playing
Initially, when I thought of role playing in this game, I found it to be non existent. How often do you see someone really trying to act out their character? But when I looked at it again, I see a great deal of role playing, even if people do not realize they are doing it. The back story of DAOC is very detailed, and the lore of the game gives you viable reasons to want to bash the helmet of an opposing realm member in, so essentially every time you RVR you are role playing. The lore of the game meshes nicely with the actual game play. If you learn the lore, there is actually a reason to be fighting, not just because you can. Many people may not even read of or know the lore in the game, never the less, it is still there, and they are participating whether they realize it or not. Even the various quests introduced tell a good deal of the game lore, but that is a whole different review.
Looking over all the features of the new frontiers free expansion, I'd have to say the only thing lacking is small group warfare. With the advent of the New PVP island that connects the realms, perhaps Mythic will bring back some of the old school 8 on 8 style PVP to mix it up with the large keep battles.