I've used
http://assuredhomeandpetcare.com/ in the past and they've been great. Quite a bit of upfront work in terms of putting your details (pet, home, contact, vacation details) into their system but once you've done it once it's easy for ever other vacation.
They do in-home and once or twice daily visits.
Good for checking mail and making sure the house is OK. As well as your pet of course.
Ours have always sent daily photos of the pet when they visited. Great peace of mind.