Humor aside, I don't care for that ep. And I don't like it, but in part because I'm a geek (so I can be fussy over details). I just don't believe that Dracula was such a celebrity among vampires and demons and yet the Watchers don't know of him, among other things. (While a memory erasure spell is--barely--plausible, I think Dracula was too much of a glory hound to resort to such measures.)
And I don't see it as a good tribute to Bram Stoker's Dracula, either. For example, Dracula could walk about in the day. It's been a LONG time since I read the book, but it hadn't been that long when I first saw the Buffy vs Dracula episode. And though I enjoyed the humor of this ep, I prefer Dracula not be played for laughs. It also felt like jumping the shark, though I think they were making a statement that this season was going to be very different from season 4...and they also needed an ep in which Dawn wasn't featured so they could throw her in at the end as a surprise.
Even with the humor that I grudgingly liked, I still disliked it enough that after the first time I didn't watch it again until I watched the entire series with others...and when it came time for season 5, I cringed as I saw Dracula...I'd actually forgotten that episode even existed. Still, it wasn't as bad on the rewatch, and since I knew not to take it seriously it was easier to laugh.
On a side note, I think Dracula's sex appeal is way overrated, and that episode drove it home for me. Once, I attended a private (home) viewing of Dracula (the black and white version with Lugosi) and it was to be an EVENT. But it was a disappointment. The one most excited loved vampires and dominant men who really hoped to be turned on by Dracula, but just sighed in disappointment (it was at the moment Dracula orders someone, "Obey!"). Part of the problem is that he was so overhyped that our expectations were too high...just as Dracula's sex appeal in the Buffy episode is overhyped which might add to my dislike of the episode.
But maybe Dracula used more magic so that even the lesbians crushed on him, as shown can happen in the Buffyverse. Of course we can assume Dracula's version was a bit more subtle than Xander's or the enchanted jacket of season 7, though it's also one more reason why the Watchers should know of him.
ETA: Yes, he shows up in the comics, though I didn't read those.