This area still has a rural feel but is a growth area. Shermansdale sits at the southern edge of Perry County,the Harrisburg area's most "country county". Perry County is finally getting it's first traffic light--due to be operation in February 2010! (Though this is at the opposite end of the county from Shermans Dale!
Clients of mine that have purchased in Perry County have been generally pleased with the school system. I encourage you to check the various specialized school report sites for specifics. While Perry County is no hotbed of drugs and crime, it seems to make its way into the papers every so often.
People attracted to Perry County value some space around them, and kind of share that "don't fence me in" sort of sentiment. While there are certainly still some good buys here, I see the pricing narrowing between Perry and the rest of the Harrisburg area. Since Shermans Dale is one of the most accesible to jobs areas of Perry County, I believe I see it even more here.
For Target/Costco/Starbucks/Barnes & Noble type shopping, you'll be doing a really easy trek to close by Mechanicsburg, Camp Hill or Harrisburg. But for a really decent hoagie on made-today bread, or a session at Curves, you can now do it all in Shermans Dale!