Yes, it's okay to drink water along with a meal. Most of the Internet discussion I've seen about water drinking along with a meal has focused on the issue of stomach acid, and whether the very acidic fluid in our stomach becomes too diluted (insufficiently acidic) when we drink water along with a meal.
There is a reasonable amount of scientific research in this area, most coming from hospital settings where researchers measured stomach acid levels in patients who either fasted and were given drinking water, or given drinking water along with a meal either before or after a surgery. While it's not normal to be staying in a hospital or to be dealing with a health problem like a surgery, it's still helpful to have high-quality studies that measure stomach acid changes in a carefully controlled way. The evidence from all of these studies suggests that stomach pH is not significantly altered by water drinking, even when a person consumes the water following an overnight fast. The amount of water consumed by patients in these studies varied, but typically fell into the 5-10 ounce range.
Even though natural stomach acid levels were not upset by drinking water in these studies, some individuals may definitely prefer to minimize or eliminate drinking water during meals, and may experience better digestion by doing so. Remember that digestion is a complicated process that depends on many factors for a healthy and comfortable outcome. These factors include: not overeating, not eating too much fat at one meal, eating in a relaxing atmosphere, and truly appreciating your food.
If drinking water with meals takes away from your enjoyment of the meal, or leaves you feeling too full too quickly, it makes sense to treat your water intake as a between-meal activity. However, if you enjoy water with your meals, I believe that there is research to support you in this practice. Don't forget that the quality of your water is extremely important! Nitrates, trihalomethanes, heavy metals, tetrachloroethylene, and pesticide residues found in unfiltered tap water have been associated with increased cancer risks in repeated research studies. Make sure that you keep your drinking water clean, either by purchasing a high-quality natural mineral water, filtering your own tap water with a high-quality carbon block filter, reverse osmosis system, and/or microfiltering process.