Complex sentence: Several other matching services, such as VolunteerMatch and Idealist, also offer virtual volunteering positions with nonprofit organizations in addition to traditional, onsite volunteering opportunities, but as yet have not released statistics relating to online volunteering through their services.
Split into simpler sentences: Several other matching services, such as VolunteerMatch and Idealist, also offer virtual volunteering positions with nonprofit organizations in addition to traditional, onsite volunteering opportunities. Idealist has not yet released statistics relating to online volunteering through their services.