Dendrobium I.D.
 

Can anyone please help identifying this Dendrobium, it is fairy tall (18-24") with long slender leaves. It would be great if you could provide me with caring tips of this Dendrobium, as many other dens. that I got around the same time have been sending out new shoots and maturing except this one...

The wxact species would be impossible without flowers, but it looks to be from the section Holochrysa. This includes D. fimbriatum, atavus, clavatum, etc. They all like good moisture and fertilizer in the growing season (Spring to Autumn) and a dryer (still lightly water!), cooler rest with much light in the Winter. Although they tend to bloom right after the rest period, some may bloom almost any time. During active growth they appreciate warmth, but are otherwise cool (Winter) to warm (Summer) growing in their natural habitat and, thus, not too picky.

For more general information you can look through these links.
IOSPE PHOTOS

The only species I would eliminate from this list is D. pulchellum, which has much heavier canes than your plant. At first glance it reminds me of D. denneanum or fimbriatum.

another group to consider is the Calcarifera, which look very similar, but you typically see left-over inflorescences. The leaves are less leathery as the Holochrysa. They are closely related.

Thanks Regelian for narrowing it down for me and the helpful caring info! I guess we will find out the exact species when it blooms.
Do you think I should worry as it is not growing since I repotted it when it arrived about a month ago.

Dendrobiums often pause when repotted. Just keep it warm and moist and you will see roots soon. If it was a recent import it needs time to adjust. Give it a misting daily, best at mid morning to mid afternoon. Later could promote fungi.
Jamie