The first time I watched this I only really caught the end credits, which consisted of little Hamtaro the hamster dancing enthusiastically to his theme song. I distinctly remember thinking, "Wow, now that's disturbing."
The second time I watched it I actually sat through an entire episode over lunch. I think I was even more disturbed that time because I realized, if I were seven years old again, I would've been totally obsessed with this show. It is exactly the kind of thing--as a fan of stuff like My Little Pony and Strawberry Shortcake--that I wouldn't have been able to get enough of as a kid.
The hamsters are adorable and all have distinct, quirky personalities. The humour is slapstick, very visual and quite entertaining. The stories, while not particularly original for cartoon fair, are light-hearted and fun.
If you've got kids and you're looking for something not as violent or cynical as everything else out there, this is a safe bet. Just be warned parents, your kids may come to you later begging you for a pet hamster.