I'd also suggest that if you don't know what the upgrade might do for you then maybe you aren't at the level of cycling ability that it will make any real difference.
The Allez is a good bike, but between expensive new wheels and a new bike, I'd pony up extra money and get a new bike that also has better wheels. Generally as you move up to higher tier levels of bike, then all the components including wheels are better relative to the lesser tier, even if it's the same base model. Though you do have to get out the the entry level pricing tiers.