Airport lounges make air travel a much better experience. Standard benefits across the board include the ability to talk to highly empowered agents that are life-savers during irregular operations when phone lines and standard agents have hour long wait times.
My biggest beef about Continental lounges (and it's quite a minor one) is the lack of self-service drinks. Northwest offers self-service alcoholic and soft drinks. By Continental getting a Coke requires going to the bartender to get it...
Here are the ones I've been to and some quick thoughts about each one:
Chicago/ORD:
Shared Continental Presidents Club/Northwest Worldclub.
Decent sized club, good wi-fi coverage. Agents are not particularly helpful. This is the only PC where the drinks are all self-service, and there is a nice selection of drinks and snacks.
Cleveland:
Continental PC (Concourse C): Nice large club, always has a plenty of complimentary newspapers (WSJ, FT, USA Today, and Cleveland Plain Dealer). The free wi-fi is great, but can get a little slow when the club is crowded, the wi-fi coverage of the club is excellent. Standard PC bar with free alcoholic and soft drinks. Agents are very nice and helpful. There is usually an empty private "office" that makes a great place to daven in. (I believe there are 6 of them).
Houston:
Continental PC (Terminal E, 1 of 5 IAH PC's and 1 of 7 Skyteam lounges): This cavernous club is awesome. 3 floors of space to stretch out in. Blazing fast wi-fi speeds. Great showers that have closets to stick your clothes into when you shower. When you're done with your shower you open the cubby to your freshly steamed and pressed clothes!
Los Angeles:
Continental PC (Terminal 6).
Medium-sized PC with very friendly agents. Located right by the Continental gates. Usually has a good amount of kosher snacks. Wi-fi is speedy, and seating is pretty good. Has very good hours of operation (5am-1am).
NYC/LaGuardia:
Continental PC (Main terminal, upstairs):
This is one of the rare clubs that is located landside instead of airside (i.e. outside security). The nice thing about being located landside is that you can access the PC even when flying other airlines in other terminals. The bad thing about being located landside is that clearing security makes it difficult to know exactly when to leave the PC. I once left the PC right when my inbound aircraft arrived but missed my flight (and lost my comp upgrade) because of a massive security line. The PC is fairly small and dark, but it's still better than waiting in the circa-1900 LGA rat-terminal. The PC is definitely in need of a renovation. To get a drink (besides the dispenser of ice water which is standard fare at all PC's) requires finding the agent hiding in the back area. There is a view of the planes at the gate, so you are able to see when your inbound aircraft arrives. The bathrooms are small and run-down, but are still better than some other public bathrooms at LGA. The speedy wi-fi and free newspapers make up for some of this PC's shortcomings.
Newark:
Continental PC (Between Terminal 2-3, 1 of 3 PC's and 1 of 5 Skyteam lounges):
This large PC is very nice with a great view of the airplanes, but often gets extremely crowded. It has showers and the shower attendant will press your clothes if you ask nicely. Agents are hit or miss, some are helpful, others have that surly NYC attitude. Wi-fi coverage can get very slow when crowded, and the signal is non-existent in the far sections of the club. Getting a drink can take a while as the bar area is always crowded. Unlike in almost any other PC, getting a fresh newspaper here is not easy. Overall a very nice looking club though.
Honolulu:
Continental PC: Very nice and spacious club with comfortable seats and couches, and great whole fruits and snacks.
Delta Crown Room Club: Small club with incredible self-service bar. Agents were rather unpleasant though.
Northwest Worldclub: In desperate need of renovation, but nice self-service drink area. This club is the only one I've ever been to without bathrooms!
Sao Paulo/GRU:
AMEX Sala Centurion.
Any AMEX charge card gets you free access to AMEX lounges.
This club is located landside. There isn't free wi-fi, but there are a few computers with free internet. Amazing looking food, alas not kosher. Nice selection of self-service soft-drinks, including my favorite Brazilian drink, Antarctica Guarana. Very nice bathrooms.
Tel Aviv:
Dan Lounge
Medium sized club with lots of (non-mehadrin) food. There is a nice selection of drinks though. The agents working there are extremely nice and helpful.